# AUTHOR <EMAIL@ADDRESS>, YEAR.
# 
# neb <nick@bebout.net>, 2011.
msgid ""
msgstr ""
"Project-Id-Version: Fedora Deployment Guide\n"
"POT-Creation-Date: 2011-02-22T00:50:46\n"
"PO-Revision-Date: 2011-03-22 15:59+0000\n"
"Last-Translator: neb <nick@bebout.net>\n"
"Language-Team: Chinese (China) (http://www.transifex.net/projects/p/fedora/team/zh_CN/)\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
"Language: zh_CN\n"
"Plural-Forms: nplurals=1; plural=0\n"

#. Tag: title
#, no-c-format
msgid "Email"
msgstr "电子邮件"

#. Tag: indexterm
#, no-c-format
msgid "<primary>email</primary> <secondary>history of</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<firstterm>Email</firstterm> was born in the 1960s. The mailbox was a file "
"in a user's home directory that was readable only by that user. Primitive "
"mail applications appended new text messages to the bottom of the file, "
"making the user wade through the constantly growing file to find any "
"particular message. This system was only capable of sending messages to "
"users on the same system."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The first network transfer of an electronic mail message file took place in "
"1971 when a computer engineer named Ray Tomlinson sent a test message "
"between two machines via ARPANET—the precursor to the Internet. "
"Communication via email soon became very popular, comprising 75 percent of "
"ARPANET's traffic in less than two years."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Today, email systems based on standardized network protocols have evolved "
"into some of the most widely used services on the Internet. &MAJOROS; offers"
" many advanced applications to serve and access email."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"This chapter reviews modern email protocols in use today, and some of the "
"programs designed to send and receive email."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Email Protocols"
msgstr "电子邮件协议"

#. Tag: indexterm
#, no-c-format
msgid "<primary>email</primary> <secondary>protocols</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Today, email is delivered using a client/server architecture. An email "
"message is created using a mail client program. This program then sends the "
"message to a server. The server then forwards the message to the recipient's"
" email server, where the message is then supplied to the recipient's email "
"client."
msgstr ""
"现在是使用客户端/服务器构架来发送电子邮件。电子邮件客户端程序可创建电子邮件信息，然后该程序将创建的信息发送给某个服务器。这个服务器接着将信息转发给接收方的电子邮件服务器，在那里将信息发送给接收方的电子邮件客户端。"

#. Tag: para
#, no-c-format
msgid ""
"To enable this process, a variety of standard network protocols allow "
"different machines, often running different operating systems and using "
"different email programs, to send and receive email."
msgstr "要启用此进程，就需要各种标准网络协议允许不同的机器访问，通常运行不同的操作系统，使用不同的电子邮件程序来发送和接收电子邮件。"

#. Tag: para
#, no-c-format
msgid ""
"The following protocols discussed are the most commonly used in the transfer"
" of email."
msgstr "以下讨论的协议是在转发电子邮件时最常用的协议。"

#. Tag: title
#, no-c-format
msgid "Mail Transport Protocols"
msgstr "邮件传输协议"

#. Tag: para
#, no-c-format
msgid ""
"Mail delivery from a client application to the server, and from an "
"originating server to the destination server, is handled by the "
"<firstterm>Simple Mail Transfer Protocol</firstterm> "
"(<firstterm>SMTP</firstterm>)."
msgstr ""
"将邮件从某个客户端程序传递到服务器，再从起始服务器到目的地服务器，这个过程是由<firstterm>简单邮件传输协议</firstterm>（<firstterm>SMTP</firstterm>）处理的。"

#. Tag: title
#, no-c-format
msgid "SMTP"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>protocols</secondary> "
"<tertiary>SMTP</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The primary purpose of SMTP is to transfer email between mail servers. "
"However, it is critical for email clients as well. To send email, the client"
" sends the message to an outgoing mail server, which in turn contacts the "
"destination mail server for delivery. For this reason, it is necessary to "
"specify an SMTP server when configuring an email client."
msgstr ""
"SMTP "
"的主要目的是在邮件服务器之间传送电子邮件，但是它对电子邮件客户端来说也很主要。要发送电子邮件，客户端会先将信息发送到一个输出电子邮件服务器，该服务器会一次联系目的地电子邮件服务器来发送邮件。因此，在配置电子邮件客户端时需要指定"
" SMTP 服务器。"

#. Tag: para
#, no-c-format
msgid ""
"Under &MAJOROS;, a user can configure an SMTP server on the local machine to"
" handle mail delivery. However, it is also possible to configure remote SMTP"
" servers for outgoing mail."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"One important point to make about the SMTP protocol is that it does not "
"require authentication. This allows anyone on the Internet to send email to "
"anyone else or even to large groups of people. It is this characteristic of "
"SMTP that makes junk email or <firstterm>spam</firstterm> possible. Imposing"
" relay restrictions limits random users on the Internet from sending email "
"through your SMTP server, to other servers on the internet. Servers that do "
"not impose such restrictions are called <firstterm>open relay</firstterm> "
"servers."
msgstr ""
"关于 SMTP 协议重要的一点就是它无需认证，这就允许互联网中的任何人可向其他一个甚至一组人发送电子邮件，也是这一点使得 SMTP "
"可能带来垃圾邮件或者使 <firstterm>spam</firstterm> 成为可能。利用中继限制可控制互联网中的随机用户通过您的 SMTP "
"服务器发送电子邮件到其它互联网中的服务器。不采用这种限制的服务器被称为<firstterm>开放中继</firstterm>服务器。"

#. Tag: para
#, no-c-format
msgid "&MAJOROS; provides the Postfix and Sendmail SMTP programs."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Mail Access Protocols"
msgstr "邮件访问协议"

#. Tag: para
#, no-c-format
msgid ""
"There are two primary protocols used by email client applications to "
"retrieve email from mail servers: the <firstterm>Post Office "
"Protocol</firstterm> (<firstterm>POP</firstterm>) and the "
"<firstterm>Internet Message Access Protocol</firstterm> "
"(<firstterm>IMAP</firstterm>)."
msgstr ""
"邮件客户端程序使用两个主要协议在邮件服务器中搜索电子邮件，它们是 <firstterm>Post Office "
"Protocol</firstterm>（<firstterm>POP</firstterm>）和 <firstterm>Internet "
"Message Access Protocol</firstterm>（<firstterm>IMAP</firstterm>）。"

#. Tag: title
#, no-c-format
msgid "POP"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>protocols</secondary> "
"<tertiary>POP</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The default POP server under &MAJOROS; is <application>Dovecot</application>"
" and is provided by the <package>dovecot</package> package."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Note: Installing the <package>dovecot</package> package"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In order to use <application>Dovecot</application>, first ensure the "
"<command>dovecot</command> package is installed on your system by running, "
"as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>yum install dovecot</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For more information on installing packages with Yum, refer to <xref linkend"
"=\"sec-Installing\" />."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"When using a <systemitem class=\"protocol\">POP</systemitem> server, email "
"messages are downloaded by email client applications. By default, most "
"<systemitem class=\"protocol\">POP</systemitem> email clients are "
"automatically configured to delete the message on the email server after it "
"has been successfully transferred, however this setting usually can be "
"changed."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<systemitem class=\"protocol\">POP</systemitem> is fully compatible with "
"important Internet messaging standards, such as <firstterm>Multipurpose "
"Internet Mail Extensions</firstterm> (<firstterm>MIME</firstterm>), which "
"allow for email attachments."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<systemitem class=\"protocol\">POP</systemitem> works best for users who "
"have one system on which to read email. It also works well for users who do "
"not have a persistent connection to the Internet or the network containing "
"the mail server. Unfortunately for those with slow network connections, "
"<systemitem class=\"protocol\">POP</systemitem> requires client programs "
"upon authentication to download the entire content of each message. This can"
" take a long time if any messages have large attachments."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The most current version of the standard <systemitem "
"class=\"protocol\">POP</systemitem> protocol is <systemitem "
"class=\"protocol\">POP3</systemitem>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"There are, however, a variety of lesser-used <systemitem "
"class=\"protocol\">POP</systemitem> protocol variants:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<emphasis>APOP</emphasis> — <systemitem class=\"protocol\">POP3</systemitem>"
" with <systemitem class=\"service\">MDS</systemitem> (Monash Directory "
"Service) authentication. An encoded hash of the user's password is sent from"
" the email client to the server rather then sending an unencrypted password."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<emphasis>KPOP</emphasis> — <systemitem class=\"protocol\">POP3</systemitem>"
" with Kerberos authentication."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<emphasis>RPOP</emphasis> — <systemitem class=\"protocol\">POP3</systemitem>"
" with <systemitem class=\"server\">RPOP</systemitem> authentication. This "
"uses a per-user ID, similar to a password, to authenticate POP requests. "
"However, this ID is not encrypted, so <systemitem "
"class=\"protocol\">RPOP</systemitem> is no more secure than standard "
"<systemitem class=\"protocol\">POP</systemitem>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For added security, it is possible to use <firstterm>Secure Socket "
"Layer</firstterm> (<firstterm>SSL</firstterm>) encryption for client "
"authentication and data transfer sessions. This can be enabled by using the "
"<command>pop3s</command> service, or by using the "
"<command>/usr/sbin/stunnel</command> application. For more information on "
"securing email communication, refer to <xref linkend=\"s2-email-security\" "
"/>."
msgstr ""

#. Tag: title
#, no-c-format
msgid "IMAP"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>protocols</secondary> "
"<tertiary>IMAP</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The default <systemitem class=\"protocol\">IMAP</systemitem> server under "
"&MAJOROS; is <application>Dovecot</application> and is provided by the "
"<package>dovecot</package> package. Refer to <xref linkend=\"s3-email-"
"protocols-pop\" /> for information on how to install "
"<application>Dovecot</application>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"When using an <systemitem class=\"protocol\">IMAP</systemitem> mail server, "
"email messages remain on the server where users can read or delete them. "
"<systemitem class=\"protocol\">IMAP</systemitem> also allows client "
"applications to create, rename, or delete mail directories on the server to "
"organize and store email."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<systemitem class=\"protocol\">IMAP</systemitem> is particularly useful for "
"users who access their email using multiple machines. The protocol is also "
"convenient for users connecting to the mail server via a slow connection, "
"because only the email header information is downloaded for messages until "
"opened, saving bandwidth. The user also has the ability to delete messages "
"without viewing or downloading them."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For convenience, <systemitem class=\"protocol\">IMAP</systemitem> client "
"applications are capable of caching copies of messages locally, so the user "
"can browse previously read messages when not directly connected to the "
"<systemitem class=\"protocol\">IMAP</systemitem> server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<systemitem class=\"protocol\">IMAP</systemitem>, like <systemitem "
"class=\"protocol\">POP</systemitem>, is fully compatible with important "
"Internet messaging standards, such as MIME, which allow for email "
"attachments."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For added security, it is possible to use <systemitem "
"class=\"protocol\">SSL</systemitem> encryption for client authentication and"
" data transfer sessions. This can be enabled by using the "
"<command>imaps</command> service, or by using the "
"<command>/usr/sbin/stunnel</command> program. For more information on "
"securing email communication, refer to <xref linkend=\"s2-email-security\" "
"/>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Other free, as well as commercial, IMAP clients and servers are available, "
"many of which extend the IMAP protocol and provide additional functionality."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Dovecot"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>mail server</secondary> "
"<tertiary>Dovecot</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The <command>imap-login</command> and <command>pop3-login</command> "
"processes which implement the <systemitem "
"class=\"protocol\">IMAP</systemitem> and <systemitem "
"class=\"protocol\">POP3</systemitem> protocols are spawned by the master "
"<systemitem class=\"daemon\">dovecot</systemitem> daemon included in the "
"<package>dovecot</package> package. The use of <systemitem "
"class=\"protocol\">IMAP</systemitem> and <systemitem "
"class=\"protocol\">POP</systemitem> is configured through the "
"<filename>/etc/dovecot/dovecot.conf</filename> configuration file; by "
"default <command>dovecot</command> runs <systemitem "
"class=\"protocol\">IMAP</systemitem> and <systemitem "
"class=\"protocol\">POP3</systemitem> together with their secure versions "
"using <systemitem class=\"protocol\">SSL</systemitem>. To configure "
"<command>dovecot</command> to use <systemitem "
"class=\"protocol\">POP</systemitem>, complete the following steps:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Edit the <filename>/etc/dovecot/dovecot.conf</filename> configuration file "
"to make sure the <literal>protocols</literal> variable is uncommented "
"(remove the hash sign (<command>#</command>) at the beginning of the line) "
"and contains the <literal>pop3</literal> argument. For example:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid "protocols = imap imaps pop3 pop3s\n"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"When the <literal>protocols</literal> variable is left commented out, "
"<command>dovecot</command> will use the default values specified for this "
"variable."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Make that change operational for the current session by running the "
"following command:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>service dovecot restart</command>\n"
"            "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Make that change operational after the next reboot by running the command:"
msgstr "运行以下命令可使修改在下次引导时可行："

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>chkconfig dovecot on</command>\n"
"            "
msgstr ""

#. Tag: title
#, no-c-format
msgid "Note"
msgstr "注记"

#. Tag: para
#, no-c-format
msgid ""
"Please note that <command>dovecot</command> only reports that it started the"
" <systemitem class=\"protocol\">IMAP</systemitem> server, but also starts "
"the <systemitem class=\"protocol\">POP3</systemitem> server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Unlike <systemitem class=\"protocol\">SMTP</systemitem>, both <systemitem "
"class=\"protocol\">IMAP</systemitem> and <systemitem "
"class=\"protocol\">POP3</systemitem> require connecting clients to "
"authenticate using a username and password. By default, passwords for both "
"protocols are passed over the network unencrypted."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To configure <systemitem class=\"protocol\">SSL</systemitem> on "
"<command>dovecot</command>:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Edit the <filename>/etc/pki/dovecot/dovecot-openssl.conf</filename> "
"configuration file as you prefer. However, in a typical installation, this "
"file does not require modification."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Rename, move or delete the files "
"<filename>/etc/pki/dovecot/certs/dovecot.pem</filename> and "
"<filename>/etc/pki/dovecot/private/dovecot.pem</filename>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Execute the <filename>/usr/libexec/dovecot/mkcert.sh</filename> script which"
" creates the <command>dovecot</command> self signed certificates. These "
"certificates are copied in the <filename>/etc/pki/dovecot/certs</filename> "
"and <filename>/etc/pki/dovecot/private</filename> directories. To implement "
"the changes, restart <command>dovecot</command>:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>service dovecot restart</command>\n"
"              "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"More details on <command>dovecot</command> can be found online at <ulink "
"url=\"http://www.dovecot.org\">http://www.dovecot.org</ulink>."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Email Program Classifications"
msgstr "电子邮件程序分类"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>program classifications</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In general, all email applications fall into at least one of three "
"classifications. Each classification plays a specific role in the process of"
" moving and managing email messages. While most users are only aware of the "
"specific email program they use to receive and send messages, each one is "
"important for ensuring that email arrives at the correct destination."
msgstr ""
"总的来说，所有电子邮件应用程序可分为三类，每一类都在移动和管理电子邮件信息过程中起到特殊的作用。虽然大多数用户只了解他们用来接收和发送信息的电子邮件程序，其实每个对确保电子邮件到达正确的目的地来说都很重要。"

#. Tag: title
#, no-c-format
msgid "Mail Transport Agent"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>types</secondary> <tertiary>Mail "
"Transport Agent</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Mail Transport Agent</primary> <see>email</see>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>MTA</primary> <see>Mail Transport Agent</see>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A <firstterm>Mail Transport Agent</firstterm> (<firstterm>MTA</firstterm>) "
"transports email messages between hosts using <systemitem "
"class=\"protocol\">SMTP</systemitem>. A message may involve several MTAs as "
"it moves to its intended destination."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"While the delivery of messages between machines may seem rather "
"straightforward, the entire process of deciding if a particular MTA can or "
"should accept a message for delivery is quite complicated. In addition, due "
"to problems from spam, use of a particular MTA is usually restricted by the "
"MTA's configuration or the access configuration for the network on which the"
" MTA resides."
msgstr ""
"尽管在机器间传递信息看起来可能非常直接了当，但决定某个特定 MTA "
"可以或者应该接受一个信息来进行传递的整个过程是相当复杂的。另外，因为垃圾邮件的问题，使用某个特定 MTA 通常会受到 MTA 配置或者 MTA "
"所在网络的配置的限制。"

#. Tag: para
#, no-c-format
msgid ""
"Many modern email client programs can act as an MTA when sending email. "
"However, this action should not be confused with the role of a true MTA. The"
" sole reason email client programs are capable of sending email like an MTA "
"is because the host running the application does not have its own MTA. This "
"is particularly true for email client programs on non-UNIX-based operating "
"systems. However, these client programs only send outbound messages to an "
"MTA they are authorized to use and do not directly deliver the message to "
"the intended recipient's email server."
msgstr ""
"很多现代电子邮件客户端程序可以在发送电子邮件时充当 MTA 的角色。但是这不会和正真的 MTA 混淆。电子邮件客户端程序可以象 MTA "
"那样发送邮件唯一的理由就是因为运行这些应用程序的主机没有它们自己的 MTA，特别是在非 UNIX "
"操作系统中的电子邮件客户端程序更是如此。但这些可用的程序只向它们认证使用的 MTA 发送外发信息，且不直接将信息传递到预期的接收电子邮件服务器。"

#. Tag: para
#, no-c-format
msgid ""
"Since &MAJOROS; offers two MTAs—<firstterm>Postfix</firstterm> and "
"<firstterm>Sendmail</firstterm>—email client programs are often not required"
" to act as an MTA. &MAJOROS; also includes a special purpose MTA called "
"<firstterm>Fetchmail</firstterm>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For more information on Postfix, Sendmail, and Fetchmail, refer to <xref "
"linkend=\"s1-email-mta\" />."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Mail Delivery Agent"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>types</secondary> <tertiary>Mail "
"Delivery Agent</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Mail Delivery Agent</primary> <see>email</see>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>MDA</primary> <see>Mail Delivery Agent</see>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A <firstterm>Mail Delivery Agent</firstterm> (<firstterm>MDA</firstterm>) is"
" invoked by the MTA to file incoming email in the proper user's mailbox. In "
"many cases, the MDA is actually a <firstterm>Local Delivery "
"Agent</firstterm> (<firstterm>LDA</firstterm>), such as "
"<command>mail</command> or Procmail."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Any program that actually handles a message for delivery to the point where "
"it can be read by an email client application can be considered an MDA. For "
"this reason, some MTAs (such as Sendmail and Postfix) can fill the role of "
"an MDA when they append new email messages to a local user's mail spool "
"file. In general, MDAs do not transport messages between systems nor do they"
" provide a user interface; MDAs distribute and sort messages on the local "
"machine for an email client application to access."
msgstr ""
"任何实际上处理将信息投递到可由电子邮件客户端应用程序读取的位置的程序都可被视为 MDA。由于这个原因，一些 MTA（比如 Sendmail 和 "
"Postfix）在向本地用户邮件池文件中添加新的电子邮件信息时可充当 MDA 的角色。一般说来，MDA 不在系统间传递信息也不提供用户界面，MDA "
"在本地机器中分发和管理信息，以便电子邮件客户端应用程序访问。"

#. Tag: title
#, no-c-format
msgid "Mail User Agent"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>types</secondary> <tertiary>Mail User "
"Agent</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Mail User Agent</primary> <see>email</see>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>MUA</primary> <see>Mail User Agent</see>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A <firstterm>Mail User Agent</firstterm> (<firstterm>MUA</firstterm>) is "
"synonymous with an email client application. An MUA is a program that, at "
"the very least, allows a user to read and compose email messages. Many MUAs "
"are capable of retrieving messages via the <systemitem "
"class=\"protocol\">POP</systemitem> or <systemitem "
"class=\"protocol\">IMAP</systemitem> protocols, setting up mailboxes to "
"store messages, and sending outbound messages to an MTA."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"MUAs may be graphical, such as <application>Evolution</application>, or have"
" simple text-based interfaces, such as <application>pine</application>."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Mail Transport Agents"
msgstr "邮件传送代理"

#. Tag: para
#, no-c-format
msgid ""
"&MAJOROS; offers two primary MTAs: Postfix and Sendmail. Postfix is "
"configured as the default MTA, although it is easy to switch the default MTA"
" to Sendmail. To switch the default MTA to Sendmail, you can either "
"uninstall Postfix or use the following command to switch to Sendmail:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"<command>~]# alternatives --config mta</command>\n"
"    "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"You can also use the following command to to enable/disable the desired "
"service:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>chkconfig <replaceable>&lt;service&gt;</replaceable> <replaceable>&lt;on/off&gt;</replaceable></command>\n"
"    "
msgstr ""

#. Tag: title
#, no-c-format
msgid "Postfix"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>email</primary> <secondary>Postfix</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Postfix</primary>"
msgstr "<primary>Postfix</primary>"

#. Tag: para
#, no-c-format
msgid ""
"Originally developed at IBM by security expert and programmer Wietse Venema,"
" Postfix is a Sendmail-compatible MTA that is designed to be secure, fast, "
"and easy to configure."
msgstr ""
"Postfix 原本由 IBM 的安全专家和程序员 Wietse Venema 开发，是一个与 Sendmail 兼容的 "
"MTA，设计的宗旨就是安全、迅速并易于配置。"

#. Tag: para
#, no-c-format
msgid ""
"To improve security, Postfix uses a modular design, where small processes "
"with limited privileges are launched by a <firstterm>master</firstterm> "
"daemon. The smaller, less privileged processes perform very specific tasks "
"related to the various stages of mail delivery and run in a change rooted "
"environment to limit the effects of attacks."
msgstr ""
"为提高安全性，Postfix "
"使用了模块设计，即带有限权限的小进程由<firstterm>主</firstterm>守护进程启动。更小的，权限更小的进程执行与邮件发送过程的不同阶段有关的非常明确的任务，并在"
" chroot 环境中运行来限制可能受到的攻击。"

#. Tag: para
#, no-c-format
msgid ""
"Configuring Postfix to accept network connections from hosts other than the "
"local computer takes only a few minor changes in its configuration file. Yet"
" for those with more complex needs, Postfix provides a variety of "
"configuration options, as well as third party add ons that make it a very "
"versatile and full-featured MTA."
msgstr ""
"要将 Postfix 配置为从主机而不是从本地计算机接受网络连接，中需要在配置文件中进行很小的改动。而对有很多复杂需求的用户，Postfix "
"提供了不同的配置选项以及第三方插入来配置一个非常详细和全功能的 MTA。"

#. Tag: para
#, no-c-format
msgid ""
"The configuration files for Postfix are human readable and support upward of"
" 250 directives. Unlike Sendmail, no macro processing is required for "
"changes to take effect and the majority of the most commonly used options "
"are described in the heavily commented files."
msgstr ""
"Postfix 的配置文件是可读的，并支持多达 250 个指令。和 Sendmail "
"不同，使修改生效无需大的进程，且大多数常用选项都在着重注释出的文件中有描述。"

#. Tag: title
#, no-c-format
msgid "The Default Postfix Installation"
msgstr "默认 Postfix 安装"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Postfix</primary> <secondary>default installation</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The Postfix executable is <filename>/usr/sbin/postfix</filename>. This "
"daemon launches all related processes needed to handle mail delivery."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Postfix stores its configuration files in the "
"<filename>/etc/postfix/</filename> directory. The following is a list of the"
" more commonly used files:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>access</filename> — Used for access control, this file specifies "
"which hosts are allowed to connect to Postfix."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>main.cf</filename> — The global Postfix configuration file. The "
"majority of configuration options are specified in this file."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>master.cf</filename> — Specifies how Postfix interacts with "
"various processes to accomplish mail delivery."
msgstr ""

#. Tag: para
#, no-c-format
msgid "<filename>transport</filename> — Maps email addresses to relay hosts."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The <filename>aliases</filename> file can be found in the "
"<filename>/etc/</filename> directory. This file is shared between Postfix "
"and Sendmail. It is a configurable list required by the mail protocol that "
"describes user ID aliases."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Important"
msgstr "重点"

#. Tag: para
#, no-c-format
msgid ""
"The default <filename>/etc/postfix/main.cf</filename> file does not allow "
"Postfix to accept network connections from a host other than the local "
"computer. For instructions on configuring Postfix as a server for other "
"clients, refer to <xref linkend=\"s3-email-mta-postfix-conf\" />."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Restart the <systemitem class=\"service\">postfix</systemitem> service after"
" changing any options in the configuration files under the "
"<filename>/etc/postfix</filename> directory in order for those changes to "
"take effect:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>service postfix restart</command>\n"
"        "
msgstr ""

#. Tag: title
#, no-c-format
msgid "Basic Postfix Configuration"
msgstr "基本 Postfix 配置"

#. Tag: para
#, no-c-format
msgid ""
"By default, Postfix does not accept network connections from any host other "
"than the local host. Perform the following steps as root to enable mail "
"delivery for other hosts on the network:"
msgstr ""
"默认情况下，Postfix 不接受来自任何主机的网络连接，而只接受来自本地主机的网络连接。以根用户身份执行以下步骤为网络中的其它主机启用邮件发送。"

#. Tag: para
#, no-c-format
msgid ""
"Edit the <filename>/etc/postfix/main.cf</filename> file with a text editor, "
"such as <command>vi</command>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Uncomment the <command>mydomain</command> line by removing the hash sign "
"(<command>#</command>), and replace <replaceable>domain.tld</replaceable> "
"with the domain the mail server is servicing, such as "
"<command>example.com</command>."
msgstr ""

#. Tag: para
#, no-c-format
msgid "Uncomment the <command>myorigin = $mydomain</command> line."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Uncomment the <command>myhostname</command> line, and replace "
"<replaceable>host.domain.tld</replaceable> with the hostname for the "
"machine."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Uncomment the <command>mydestination = $myhostname, "
"localhost.$mydomain</command> line."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Uncomment the <command>mynetworks</command> line, and replace "
"<replaceable>168.100.189.0/28</replaceable> with a valid network setting for"
" hosts that can connect to the server."
msgstr ""

#. Tag: para
#, no-c-format
msgid "Uncomment the <command>inet_interfaces = all</command> line."
msgstr ""

#. Tag: para
#, no-c-format
msgid "Comment the <command>inet_interfaces = localhost</command> line."
msgstr ""

#. Tag: para
#, no-c-format
msgid "Restart the <command>postfix</command> service."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Once these steps are complete, the host accepts outside emails for delivery."
msgstr "完成这些步骤后，主机就可接受外部邮件发送。"

#. Tag: para
#, no-c-format
msgid ""
"Postfix has a large assortment of configuration options. One of the best "
"ways to learn how to configure Postfix is to read the comments within the "
"<filename>/etc/postfix/main.cf</filename> configuration file. Additional "
"resources including information about Postfix configuration, SpamAssassin "
"integration, or detailed descriptions of the "
"<filename>/etc/postfix/main.cf</filename> parameters are available online at"
" <ulink url=\"http://www.postfix.org/\">http://www.postfix.org/</ulink>."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Using Postfix with LDAP"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Postfix can use an <systemitem class=\"protocol\">LDAP</systemitem> "
"directory as a source for various lookup tables (e.g.: "
"<filename>aliases</filename>, <filename>virtual</filename>, "
"<filename>canonical</filename>, etc.). This allows <systemitem "
"class=\"protocol\">LDAP</systemitem> to store hierarchical user information "
"and Postfix to only be given the result of <systemitem "
"class=\"protocol\">LDAP</systemitem> queries when needed. By not storing "
"this information locally, administrators can easily maintain it."
msgstr ""

#. Tag: title
#, no-c-format
msgid "<filename>The /etc/aliases</filename> lookup example"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The following is a basic example for using <systemitem "
"class=\"protocol\">LDAP</systemitem> to look up the "
"<filename>/etc/aliases</filename> file. Make sure your "
"<filename>/etc/postfix/main.cf</filename> contains the following:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"alias_maps = hash:/etc/aliases, ldap:/etc/postfix/ldap-aliases.cf\n"
"          "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Create a <filename>/etc/postfix/ldap-aliases.cf</filename> file if you do "
"not have one created already and make sure it contains the following:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"server_host = <replaceable>ldap.example.com</replaceable>\n"
"search_base = dc=<replaceable>example</replaceable>, dc=<replaceable>com</replaceable>\n"
"          "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"where <parameter>ldap.example.com</parameter>, "
"<parameter>example</parameter>, and <parameter>com</parameter> are "
"parameters that need to be replaced with specification of an existing "
"available <systemitem class=\"protocol\">LDAP</systemitem> server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The /<filename>etc/postfix/ldap-aliases.cf</filename> file can specify "
"various parameters, including parameters that enable <systemitem "
"class=\"protocol\">LDAP</systemitem> <systemitem "
"class=\"protocol\">SSL</systemitem> and <systemitem "
"class=\"protocol\">STARTTLS</systemitem>. For more information, refer to the"
" <command>ldap_table(5)</command> man page."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For more information on <systemitem class=\"protocol\">LDAP</systemitem>, "
"refer to <xref linkend=\"ch-Lightweight_Directory_Access_Protocol_LDAP\" />."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Sendmail"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>email</primary> <secondary>Sendmail</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Sendmail</primary>"
msgstr "<primary>Sendmail</primary>"

#. Tag: para
#, no-c-format
msgid ""
"Sendmail's core purpose, like other MTAs, is to safely transfer email among "
"hosts, usually using the <systemitem class=\"protocol\">SMTP</systemitem> "
"protocol. However, Sendmail is highly configurable, allowing control over "
"almost every aspect of how email is handled, including the protocol used. "
"Many system administrators elect to use Sendmail as their MTA due to its "
"power and scalability."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Purpose and Limitations"
msgstr "目的和限制"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Sendmail</primary> <secondary>purpose</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Sendmail</primary> <secondary>limitations</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"It is important to be aware of what Sendmail is and what it can do, as "
"opposed to what it is not. In these days of monolithic applications that "
"fulfill multiple roles, Sendmail may seem like the only application needed "
"to run an email server within an organization. Technically, this is true, as"
" Sendmail can spool mail to each users' directory and deliver outbound mail "
"for users. However, most users actually require much more than simple email "
"delivery. Users usually want to interact with their email using an MUA, that"
" uses <systemitem class=\"protocol\">POP</systemitem> or <systemitem "
"class=\"protocol\">IMAP</systemitem>, to download their messages to their "
"local machine. Or, they may prefer a Web interface to gain access to their "
"mailbox. These other applications can work in conjunction with Sendmail, but"
" they actually exist for different reasons and can operate separately from "
"one another."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"It is beyond the scope of this section to go into all that Sendmail should "
"or could be configured to do. With literally hundreds of different options "
"and rule sets, entire volumes have been dedicated to helping explain "
"everything that can be done and how to fix things that go wrong. Refer to "
"the <xref linkend=\"s1-email-additional-resources\" /> for a list of "
"Sendmail resources."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"This section reviews the files installed with Sendmail by default and "
"reviews basic configuration changes, including how to stop unwanted email "
"(spam) and how to extend Sendmail with the <firstterm>Lightweight Directory "
"Access Protocol (LDAP)</firstterm>."
msgstr ""
"这一部分总结在默认安装 Sendmail "
"时安装的文件以及修改基本配置，其中包括如何停止不想要的电子邮件（垃圾邮件）和如何用<firstterm>轻量级目录访问协议（LDAP）</firstterm>扩展"
" Sendmail。"

#. Tag: title
#, no-c-format
msgid "The Default Sendmail Installation"
msgstr "默认 Sendmail 安装"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Sendmail</primary> <secondary>default installation</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In order to use Sendmail, first ensure the <package>sendmail</package> "
"package is installed on your system by running, as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid "~]# <command>yum install sendmail</command>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In order to configure Sendmail, ensure the <package>sendmail-cf</package> "
"package is installed on your system by running, as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid "~]# <command>yum install sendmail-cf</command>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Before using Sendmail, the default MTA has to be switched from Postfix. For "
"more information how to switch the default MTA refer to <xref linkend=\"s1"
"-email-mta\" />."
msgstr ""

#. Tag: para
#, no-c-format
msgid "The Sendmail executable is <filename>/usr/sbin/sendmail</filename>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Sendmail's lengthy and detailed configuration file is "
"<filename>/etc/mail/sendmail.cf</filename>. Avoid editing the "
"<filename>sendmail.cf</filename> file directly. To make configuration "
"changes to Sendmail, edit the <filename>/etc/mail/sendmail.mc</filename> "
"file, back up the original <filename>/etc/mail/sendmail.cf</filename>, and "
"use the following alternatives to generate a new configuration file:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Use the included makefile in <filename>/etc/mail/</filename> (<command>~]# "
"make all -C /etc/mail/</command>) to create a new "
"<filename>/etc/mail/sendmail.cf</filename> configuration file. All other "
"generated files in <filename>/etc/mail</filename> (db files) will be "
"regenerated if needed. The old makemap commands are still usable. The make "
"command will automatically be used by <command>service sendmail start | "
"restart | reload</command>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Alternatively you may use the <command>m4</command> macro processor to "
"create a new <filename>/etc/mail/sendmail.cf</filename>. The "
"<command>m4</command> macro processor is not installed by default. Before "
"using it to create <filename>/etc/mail/sendmail.cf</filename>, install the "
"<package>m4</package> package as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>yum install m4</command>\n"
"            "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"More information on configuring Sendmail can be found in <xref linkend=\"s3"
"-email-mta-sendmail-changes\" />."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Various Sendmail configuration files are installed in the "
"<filename>/etc/mail/</filename> directory including:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>access</filename> — Specifies which systems can use Sendmail for "
"outbound email."
msgstr ""

#. Tag: para
#, no-c-format
msgid "<filename>domaintable</filename> — Specifies domain name mapping."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>local-host-names</filename> — Specifies aliases for the host."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>mailertable</filename> — Specifies instructions that override "
"routing for particular domains."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>virtusertable</filename> — Specifies a domain-specific form of "
"aliasing, allowing multiple virtual domains to be hosted on one machine."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Several of the configuration files in <filename>/etc/mail/</filename>, such "
"as <filename>access</filename>, <filename>domaintable</filename>, "
"<filename>mailertable</filename> and <filename>virtusertable</filename>, "
"must actually store their information in database files before Sendmail can "
"use any configuration changes. To include any changes made to these "
"configurations in their database files, run the following command, as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>makemap hash /etc/mail/<replaceable>&lt;name&gt;</replaceable> &lt; /etc/mail/<replaceable>&lt;name&gt;</replaceable></command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"where <replaceable>&lt;name&gt;</replaceable> represents the name of the "
"configuration file to be updated. You may also restart the <systemitem "
"class=\"service\">sendmail</systemitem> service for the changes to take "
"effect by running:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>service sendmail restart</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For example, to have all emails addressed to the "
"<filename>example.com</filename> domain delivered to <email>bob@other-"
"example.com</email>, add the following line to the "
"<filename>virtusertable</filename> file:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"<command>@example.com bob@other-example.com</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To finalize the change, the <filename>virtusertable.db</filename> file must "
"be updated:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>makemap hash /etc/mail/virtusertable &lt; /etc/mail/virtusertable</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Sendmail will create an updated <filename>virtusertable.db</filename> file "
"containing the new configuration."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Common Sendmail Configuration Changes"
msgstr "通用 Sendmail 配置修改"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Sendmail</primary> <secondary>common configuration "
"changes</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Sendmail</primary> <secondary>with UUCP</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"When altering the Sendmail configuration file, it is best not to edit an "
"existing file, but to generate an entirely new "
"<filename>/etc/mail/sendmail.cf</filename> file."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Caution"
msgstr "小心"

#. Tag: para
#, no-c-format
msgid ""
"Before changing the <filename>sendmail.cf</filename> file, it is a good idea"
" to create a backup copy."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To add the desired functionality to Sendmail, edit the "
"<filename>/etc/mail/sendmail.mc</filename> file as root. Once you are "
"finished, restart the <systemitem class=\"service\">sendmail</systemitem> "
"service and, if the <package>m4</package> package is installed, the "
"<command>m4</command> macro processor will automatically generate a new "
"<filename>sendmail.cf</filename> configuration file:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The default <filename>sendmail.cf</filename> file does not allow Sendmail to"
" accept network connections from any host other than the local computer. To "
"configure Sendmail as a server for other clients, edit the "
"<filename>/etc/mail/sendmail.mc</filename> file, and either change the "
"address specified in the <command>Addr=</command> option of the "
"<command>DAEMON_OPTIONS</command> directive from "
"<command>127.0.0.1</command> to the IP address of an active network device "
"or comment out the <command>DAEMON_OPTIONS</command> directive all together "
"by placing <command>dnl</command> at the beginning of the line. When "
"finished, regenerate <filename>/etc/mail/sendmail.cf</filename> by "
"restarting the service"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>service sendmail restart</command>\n"
"          "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The default configuration which ships with &MAJOROS; works for most "
"<systemitem class=\"protocol\">SMTP</systemitem>-only sites. However, it "
"does not work for <firstterm>UUCP</firstterm> (<firstterm>UNIX-to-UNIX Copy "
"Protocol</firstterm>) sites. If using UUCP mail transfers, the "
"<filename>/etc/mail/sendmail.mc</filename> file must be reconfigured and a "
"new <filename>/etc/mail/sendmail.cf</filename> file must be generated."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Consult the <filename>/usr/share/sendmail-cf/README</filename> file before "
"editing any files in the directories under the <filename>/usr/share"
"/sendmail-cf</filename> directory, as they can affect the future "
"configuration of the <filename>/etc/mail/sendmail.cf</filename> file."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Masquerading"
msgstr "伪装"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Sendmail</primary> <secondary>aliases</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Sendmail</primary> <secondary>masquerading</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"One common Sendmail configuration is to have a single machine act as a mail "
"gateway for all machines on the network. For instance, a company may want to"
" have a machine called <computeroutput>mail.example.com</computeroutput> "
"that handles all of their email and assigns a consistent return address to "
"all outgoing mail."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In this situation, the Sendmail server must masquerade the machine names on "
"the company network so that their return address is "
"<computeroutput>user@example.com</computeroutput> instead of "
"<computeroutput>user@host.example.com</computeroutput>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To do this, add the following lines to "
"<filename>/etc/mail/sendmail.mc</filename>:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"FEATURE(always_add_domain)dnl\n"
"FEATURE(`masquerade_entire_domain')dnl\n"
"FEATURE(`masquerade_envelope')dnl\n"
"FEATURE(`allmasquerade')dnl\n"
"MASQUERADE_AS(`bigcorp.com.')dnl\n"
"MASQUERADE_DOMAIN(`bigcorp.com.')dnl\n"
"MASQUERADE_AS(bigcorp.com)dnl\n"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"After generating a new <filename>sendmail.cf</filename> using the "
"<command>m4</command> macro processor, this configuration makes all mail "
"from inside the network appear as if it were sent from "
"<computeroutput>bigcorp.com</computeroutput>."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Stopping Spam"
msgstr "终止垃圾邮件"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Sendmail</primary> <secondary>spam</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Email spam can be defined as unnecessary and unwanted email received by a "
"user who never requested the communication. It is a disruptive, costly, and "
"widespread abuse of Internet communication standards."
msgstr "电子邮件垃圾可被定义为从那些从未请求沟通的用户处接收到的没有必要和不想收到的电子邮件。这是对互联网沟通标准的破坏性的、浪费的和广泛的滥用。"

#. Tag: para
#, no-c-format
msgid ""
"Sendmail makes it relatively easy to block new spamming techniques being "
"employed to send junk email. It even blocks many of the more usual spamming "
"methods by default. Main anti-spam features available in sendmail are "
"<firstterm>header checks</firstterm>, <firstterm>relaying denial</firstterm>"
" (default from version 8.9), <firstterm>access database and sender "
"information checks</firstterm>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For example, forwarding of <systemitem class=\"protocol\">SMTP</systemitem> "
"messages, also called relaying, has been disabled by default since Sendmail "
"version 8.9. Before this change occurred, Sendmail directed the mail host "
"(<filename>x.edu</filename>) to accept messages from one party "
"(<filename>y.com</filename>) and sent them to a different party "
"(<filename>z.net</filename>). Now, however, Sendmail must be configured to "
"permit any domain to relay mail through the server. To configure relay "
"domains, edit the <filename>/etc/mail/relay-domains</filename> file and "
"restart Sendmail"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"However, many times users are bombarded with spam from other servers "
"throughout the Internet. In these instances, Sendmail's access control "
"features available through the <filename>/etc/mail/access</filename> file "
"can be used to prevent connections from unwanted hosts. The following "
"example illustrates how this file can be used to both block and specifically"
" allow access to the Sendmail server:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"<command>badspammer.com ERROR:550 \"Go away and do not spam us anymore\" tux.badspammer.com OK 10.0 RELAY</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"This example shows that any email sent from "
"<filename>badspammer.com</filename> is blocked with a 550 RFC-821 compliant "
"error code, with a message sent back to the spammer. Email sent from the "
"<filename>tux.badspammer.com</filename> sub-domain, is accepted. The last "
"line shows that any email sent from the 10.0.*.* network can be relayed "
"through the mail server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Because the <filename>/etc/mail/access.db</filename> file is a database, use"
" the <command>makemap</command> command to update any changes. Do this using"
" the following command as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>makemap hash /etc/mail/access &lt; /etc/mail/access</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Message header analysis allows you to reject mail based on header contents. "
"<systemitem class=\"protocol\">SMTP</systemitem> servers store information "
"about an email's journey in the message header. As the message travels from "
"one MTA to another, each puts in a <literal>Received</literal> header above "
"all the other <literal>Received</literal> headers. It is important to note "
"that this information may be altered by spammers."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The above examples only represent a small part of what Sendmail can do in "
"terms of allowing or blocking access. Refer to the <filename>/usr/share"
"/sendmail-cf/README</filename> for more information and examples."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Since Sendmail calls the Procmail MDA when delivering mail, it is also "
"possible to use a spam filtering program, such as SpamAssassin, to identify "
"and file spam for users. Refer to <xref linkend=\"s3-email-mda-spam\" /> for"
" more information about using SpamAssassin."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Using Sendmail with LDAP"
msgstr "使用带 LDAP 的 Sendmail？"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Sendmail</primary> <secondary>LDAP and</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Using <systemitem class=\"protocol\">LDAP</systemitem> is a very quick and "
"powerful way to find specific information about a particular user from a "
"much larger group. For example, an <systemitem "
"class=\"protocol\">LDAP</systemitem> server can be used to look up a "
"particular email address from a common corporate directory by the user's "
"last name. In this kind of implementation, <systemitem "
"class=\"protocol\">LDAP</systemitem> is largely separate from Sendmail, with"
" <systemitem class=\"protocol\">LDAP</systemitem> storing the hierarchical "
"user information and Sendmail only being given the result of <systemitem "
"class=\"protocol\">LDAP</systemitem> queries in pre-addressed email "
"messages."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"However, Sendmail supports a much greater integration with <systemitem "
"class=\"protocol\">LDAP</systemitem>, where it uses <systemitem "
"class=\"protocol\">LDAP</systemitem> to replace separately maintained files,"
" such as <filename>/etc/aliases</filename> and "
"<filename>/etc/mail/virtusertables</filename>, on different mail servers "
"that work together to support a medium- to enterprise-level organization. In"
" short, <systemitem class=\"protocol\">LDAP</systemitem> abstracts the mail "
"routing level from Sendmail and its separate configuration files to a "
"powerful <systemitem class=\"protocol\">LDAP</systemitem> cluster that can "
"be leveraged by many different applications."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The current version of Sendmail contains support for <systemitem "
"class=\"protocol\">LDAP</systemitem>. To extend the Sendmail server using "
"<systemitem class=\"protocol\">LDAP</systemitem>, first get an <systemitem "
"class=\"protocol\">LDAP</systemitem> server, such as "
"<application>OpenLDAP</application>, running and properly configured. Then "
"edit the <filename>/etc/mail/sendmail.mc</filename> to include the "
"following:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"LDAPROUTE_DOMAIN('<replaceable>yourdomain.com</replaceable>')dnl\n"
"FEATURE('ldap_routing')dnl\n"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"This is only for a very basic configuration of Sendmail with <systemitem "
"class=\"protocol\">LDAP</systemitem>. The configuration can differ greatly "
"from this depending on the implementation of <systemitem "
"class=\"protocol\">LDAP</systemitem>, especially when configuring several "
"Sendmail machines to use a common <systemitem "
"class=\"protocol\">LDAP</systemitem> server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Consult <filename>/usr/share/sendmail-cf/README</filename> for detailed "
"<systemitem class=\"protocol\">LDAP</systemitem> routing configuration "
"instructions and examples."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Next, recreate the <filename>/etc/mail/sendmail.cf</filename> file by "
"running the <command>m4</command> macro processor and again restarting "
"Sendmail. Refer to <xref linkend=\"s3-email-mta-sendmail-changes\" /> for "
"instructions."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Fetchmail"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>email</primary> <secondary>Fetchmail</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Fetchmail</primary>"
msgstr "<primary>Fetchmail</primary>"

#. Tag: para
#, no-c-format
msgid ""
"Fetchmail is an MTA which retrieves email from remote servers and delivers "
"it to the local MTA. Many users appreciate the ability to separate the "
"process of downloading their messages located on a remote server from the "
"process of reading and organizing their email in an MUA. Designed with the "
"needs of dial-up users in mind, Fetchmail connects and quickly downloads all"
" of the email messages to the mail spool file using any number of protocols,"
" including <systemitem class=\"protocol\">POP3</systemitem> and <systemitem "
"class=\"protocol\">IMAP</systemitem>. It can even forward email messages to "
"an <systemitem class=\"protocol\">SMTP</systemitem> server, if necessary."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Note: Installing the <package>fetchmail</package> package"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In order to use <application>Fetchmail</application>, first ensure the "
"<package>fetchmail</package> package is installed on your system by running,"
" as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid "~]# <command>yum install fetchmail</command>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Fetchmail is configured for each user through the use of a "
"<filename>.fetchmailrc</filename> file in the user's home directory. If it "
"does not already exist, create the <filename>.fetchmailrc</filename> file in"
" your home directory"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Using preferences in the <filename>.fetchmailrc</filename> file, Fetchmail "
"checks for email on a remote server and downloads it. It then delivers it to"
" port <constant>25</constant> on the local machine, using the local MTA to "
"place the email in the correct user's spool file. If Procmail is available, "
"it is launched to filter the email and place it in a mailbox so that it can "
"be read by an MUA."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Fetchmail Configuration Options"
msgstr "Fetchmail 配置选项"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Fetchmail</primary> <secondary>configuration options</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary> <filename>.fetchmailrc</filename> </primary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Although it is possible to pass all necessary options on the command line to"
" check for email on a remote server when executing Fetchmail, using a "
"<filename>.fetchmailrc</filename> file is much easier. Place any desired "
"configuration options in the <filename>.fetchmailrc</filename> file for "
"those options to be used each time the <command>fetchmail</command> command "
"is issued. It is possible to override these at the time Fetchmail is run by "
"specifying that option on the command line."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A user's <filename>.fetchmailrc</filename> file contains three classes of "
"configuration options:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<emphasis>global options</emphasis> — Gives Fetchmail instructions that "
"control the operation of the program or provide settings for every "
"connection that checks for email."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<emphasis>server options</emphasis> — Specifies necessary information about "
"the server being polled, such as the hostname, as well as preferences for "
"specific email servers, such as the port to check or number of seconds to "
"wait before timing out. These options affect every user using that server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<emphasis>user options</emphasis> — Contains information, such as username "
"and password, necessary to authenticate and check for email using a "
"specified email server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Global options appear at the top of the <filename>.fetchmailrc</filename> "
"file, followed by one or more server options, each of which designate a "
"different email server that Fetchmail should check. User options follow "
"server options for each user account checking that email server. Like server"
" options, multiple user options may be specified for use with a particular "
"server as well as to check multiple email accounts on the same server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Server options are called into service in the "
"<filename>.fetchmailrc</filename> file by the use of a special option verb, "
"<command>poll</command> or <command>skip</command>, that precedes any of the"
" server information. The <command>poll</command> action tells Fetchmail to "
"use this server option when it is run, which checks for email using the "
"specified user options. Any server options after a <command>skip</command> "
"action, however, are not checked unless this server's hostname is specified "
"when Fetchmail is invoked. The <command>skip</command> option is useful when"
" testing configurations in the <filename>.fetchmailrc</filename> file "
"because it only checks skipped servers when specifically invoked, and does "
"not affect any currently working configurations."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The following is a sample example of a <filename>.fetchmailrc</filename> "
"file:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"set postmaster \"user1\"\n"
"set bouncemail\n"
"\n"
"poll pop.domain.com proto pop3\n"
"    user 'user1' there with password 'secret' is user1 here\n"
"\n"
"poll mail.domain2.com\n"
"    user 'user5' there with password 'secret2' is user1 here\n"
"    user 'user7' there with password 'secret3' is user1 here"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In this example, the global options specify that the user is sent email as a"
" last resort (<command>postmaster</command> option) and all email errors are"
" sent to the postmaster instead of the sender (<command>bouncemail</command>"
" option). The <command>set</command> action tells Fetchmail that this line "
"contains a global option. Then, two email servers are specified, one set to "
"check using <systemitem class=\"protocol\">POP3</systemitem>, the other for "
"trying various protocols to find one that works. Two users are checked using"
" the second server option, but all email found for any user is sent to "
"<command>user1</command>'s mail spool. This allows multiple mailboxes to be "
"checked on multiple servers, while appearing in a single MUA inbox. Each "
"user's specific information begins with the <command>user</command> action."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Users are not required to place their password in the "
"<filename>.fetchmailrc</filename> file. Omitting the <command>with password "
"'&lt;password&gt;'</command> section causes Fetchmail to ask for a password "
"when it is launched."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Fetchmail has numerous global, server, and local options. Many of these "
"options are rarely used or only apply to very specific situations. The "
"<filename>fetchmail</filename> man page explains each option in detail, but "
"the most common ones are listed in the following three sections."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Global Options"
msgstr "全局选项"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Fetchmail</primary> <secondary>configuration options</secondary> "
"<tertiary>global options</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>ch-email <filename>.fetchmailrc</filename> </primary> "
"<secondary>global options</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Each global option should be placed on a single line after a "
"<command>set</command> action."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>daemon <replaceable>&lt;seconds&gt;</replaceable> </command> — "
"Specifies daemon-mode, where Fetchmail stays in the background. Replace "
"<replaceable>&lt;seconds&gt;</replaceable> with the number of seconds "
"Fetchmail is to wait before polling the server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>postmaster</command> — Specifies a local user to send mail to in "
"case of delivery problems."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>syslog</command> — Specifies the log file for errors and status "
"messages. By default, this is <filename>/var/log/maillog</filename>."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Server Options"
msgstr "服务器选项"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Fetchmail</primary> <secondary>configuration options</secondary> "
"<tertiary>server options</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary> <filename>.fetchmailrc</filename> </primary> <secondary>server "
"options</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Server options must be placed on their own line in "
"<filename>.fetchmailrc</filename> after a <command>poll</command> or "
"<command>skip</command> action."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>auth <replaceable>&lt;auth-type&gt;</replaceable> </command> — "
"Replace <replaceable>&lt;auth-type&gt;</replaceable> with the type of "
"authentication to be used. By default, <command>password</command> "
"authentication is used, but some protocols support other types of "
"authentication, including <command>kerberos_v5</command>, "
"<command>kerberos_v4</command>, and <command>ssh</command>. If the "
"<command>any</command> authentication type is used, Fetchmail first tries "
"methods that do not require a password, then methods that mask the password,"
" and finally attempts to send the password unencrypted to authenticate to "
"the server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>interval <replaceable>&lt;number&gt;</replaceable> </command> — "
"Polls the specified server every "
"<command><replaceable>&lt;number&gt;</replaceable> </command> of times that "
"it checks for email on all configured servers. This option is generally used"
" for email servers where the user rarely receives messages."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>port <replaceable>&lt;port-number&gt;</replaceable> </command> — "
"Replace <replaceable>&lt;port-number&gt;</replaceable> with the port number."
" This value overrides the default port number for the specified protocol."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>proto <replaceable>&lt;protocol&gt;</replaceable> </command> — "
"Replace <replaceable>&lt;protocol&gt;</replaceable> with the protocol, such "
"as <command>pop3</command> or <command>imap</command>, to use when checking "
"for messages on the server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>timeout <replaceable>&lt;seconds&gt;</replaceable> </command> — "
"Replace <replaceable>&lt;seconds&gt;</replaceable> with the number of "
"seconds of server inactivity after which Fetchmail gives up on a connection "
"attempt. If this value is not set, a default of <command>300</command> "
"seconds is assumed."
msgstr ""

#. Tag: title
#, no-c-format
msgid "User Options"
msgstr "用户选项"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Fetchmail</primary> <secondary>configuration options</secondary> "
"<tertiary>user options</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary> <filename>.fetchmailrc</filename> </primary> <secondary>user "
"options</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"User options may be placed on their own lines beneath a server option or on "
"the same line as the server option. In either case, the defined options must"
" follow the <command>user</command> option (defined below)."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>fetchall</command> — Orders Fetchmail to download all messages in "
"the queue, including messages that have already been viewed. By default, "
"Fetchmail only pulls down new messages."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>fetchlimit <replaceable>&lt;number&gt;</replaceable> </command> — "
"Replace <replaceable>&lt;number&gt;</replaceable> with the number of "
"messages to be retrieved before stopping."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>flush</command> — Deletes all previously viewed messages in the "
"queue before retrieving new messages."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>limit <replaceable>&lt;max-number-bytes&gt;</replaceable> "
"</command> — Replace <replaceable>&lt;max-number-bytes&gt;</replaceable> "
"with the maximum size in bytes that messages are allowed to be when "
"retrieved by Fetchmail. This option is useful with slow network links, when "
"a large message takes too long to download."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>password '<replaceable>&lt;password&gt;</replaceable>'</command> — "
"Replace <replaceable>&lt;password&gt;</replaceable> with the user's "
"password."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>preconnect \"<replaceable>&lt;command&gt;</replaceable>\"</command>"
" — Replace <replaceable>&lt;command&gt;</replaceable> with a command to be "
"executed before retrieving messages for the user."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>postconnect "
"\"<replaceable>&lt;command&gt;</replaceable>\"</command> — Replace "
"<replaceable>&lt;command&gt;</replaceable> with a command to be executed "
"after retrieving messages for the user."
msgstr ""

#. Tag: para
#, no-c-format
msgid "<command>ssl</command> — Activates SSL encryption."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>user \"<replaceable>&lt;username&gt;</replaceable>\"</command> — "
"Replace <replaceable>&lt;username&gt;</replaceable> with the username used "
"by Fetchmail to retrieve messages. <emphasis>This option must precede all "
"other user options.</emphasis>"
msgstr ""

#. Tag: title
#, no-c-format
msgid "Fetchmail Command Options"
msgstr "Fetchmail 命令选项"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Fetchmail</primary> <secondary>command options</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Most Fetchmail options used on the command line when executing the "
"<command>fetchmail</command> command mirror the "
"<filename>.fetchmailrc</filename> configuration options. In this way, "
"Fetchmail may be used with or without a configuration file. These options "
"are not used on the command line by most users because it is easier to leave"
" them in the <filename>.fetchmailrc</filename> file."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"There may be times when it is desirable to run the "
"<command>fetchmail</command> command with other options for a particular "
"purpose. It is possible to issue command options to temporarily override a "
"<filename>.fetchmailrc</filename> setting that is causing an error, as any "
"options specified at the command line override configuration file options."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Informational or Debugging Options"
msgstr "报告或者故障排除选项"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Fetchmail</primary> <secondary>command options</secondary> "
"<tertiary>informational</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Certain options used after the <command>fetchmail</command> command can "
"supply important information."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>--configdump</command> — Displays every possible option based on "
"information from <filename>.fetchmailrc</filename> and Fetchmail defaults. "
"No email is retrieved for any users when using this option."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>-s</command> — Executes Fetchmail in silent mode, preventing any "
"messages, other than errors, from appearing after the "
"<command>fetchmail</command> command."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>-v</command> — Executes Fetchmail in verbose mode, displaying every"
" communication between Fetchmail and remote email servers."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>-V</command> — Displays detailed version information, lists its "
"global options, and shows settings to be used with each user, including the "
"email protocol and authentication method. No email is retrieved for any "
"users when using this option."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Special Options"
msgstr "特殊选项"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Fetchmail</primary> <secondary>command options</secondary> "
"<tertiary>special</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"These options are occasionally useful for overriding defaults often found in"
" the <filename>.fetchmailrc</filename> file."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>-a</command> — Fetchmail downloads all messages from the remote "
"email server, whether new or previously viewed. By default, Fetchmail only "
"downloads new messages."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>-k</command> — Fetchmail leaves the messages on the remote email "
"server after downloading them. This option overrides the default behavior of"
" deleting messages after downloading them."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>-l <replaceable>&lt;max-number-bytes&gt;</replaceable> </command> —"
" Fetchmail does not download any messages over a particular size and leaves "
"them on the remote email server."
msgstr ""

#. Tag: para
#, no-c-format
msgid "<command>--quit</command> — Quits the Fetchmail daemon process."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"More commands and <filename>.fetchmailrc</filename> options can be found in "
"the <command>fetchmail</command> man page."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Mail Transport Agent (MTA) Configuration"
msgstr "邮件传递代理（MTA）配置"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Mail Transport Agent</primary> <see>MTA</see>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>MTA</primary> <secondary>setting default</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>MTA</primary> <secondary>switching with <application>Mail Transport"
" Agent Switcher</application> </secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary> <application>Mail Transport Agent Switcher</application> "
"</primary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Mail User Agent</primary>"
msgstr "<primary>邮件用户代理</primary>"

#. Tag: indexterm
#, no-c-format
msgid "<primary>MUA</primary>"
msgstr "<primary>MUA</primary>"

#. Tag: para
#, no-c-format
msgid ""
"A <firstterm>Mail Transport Agent</firstterm> (MTA) is essential for sending"
" email. A <firstterm>Mail User Agent</firstterm> (MUA) such as "
"<application>Evolution</application>, "
"<application>Thunderbird</application>, and <application>Mutt</application>,"
" is used to read and compose email. When a user sends an email from an MUA, "
"the message is handed off to the MTA, which sends the message through a "
"series of MTAs until it reaches its destination."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Even if a user does not plan to send email from the system, some automated "
"tasks or system programs might use the <command>/bin/mail</command> command "
"to send email containing log messages to the root user of the local system."
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>sendmail</primary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>postfix</primary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"&MAJOROSVER; provides two MTAs: Postfix and Sendmail. If both are installed,"
" Postfix is the default MTA."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Mail Delivery Agents"
msgstr "邮件发送代理"

#. Tag: para
#, no-c-format
msgid ""
"&MAJOROS; includes two primary MDAs, Procmail and <command>mail</command>. "
"Both of the applications are considered LDAs and both move email from the "
"MTA's spool file into the user's mailbox. However, Procmail provides a "
"robust filtering system."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"This section details only Procmail. For information on the "
"<command>mail</command> command, consult its man page (<command>man "
"mail</command>)."
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>email</primary> <secondary>Procmail</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>Procmail</primary>"
msgstr "<primary>Procmail</primary>"

#. Tag: para
#, no-c-format
msgid ""
"Procmail delivers and filters email as it is placed in the mail spool file "
"of the localhost. It is powerful, gentle on system resources, and widely "
"used. Procmail can play a critical role in delivering email to be read by "
"email client applications."
msgstr ""
"Procmail 发送并过滤电子邮件，因为它会位于本地主机的邮件池文件。它的功能很强大，对系统资源消耗小，且可广泛使用。Procmail "
"在通过电子邮件客户应用程序发送可读电子邮件中起到了很重要的作用。"

#. Tag: para
#, no-c-format
msgid ""
"Procmail can be invoked in several different ways. Whenever an MTA places an"
" email into the mail spool file, Procmail is launched. Procmail then filters"
" and files the email for the MUA and quits. Alternatively, the MUA can be "
"configured to execute Procmail any time a message is received so that "
"messages are moved into their correct mailboxes. By default, the presence of"
" <filename>/etc/procmailrc</filename> or of a "
"<filename>~/.procmailrc</filename> file (also called an "
"<firstterm>rc</firstterm> file) in the user's home directory invokes "
"Procmail whenever an MTA receives a new message."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"By default, no system-wide <filename>rc</filename> files exist in the "
"<filename>/etc/</filename> directory and no <filename>.procmailrc</filename>"
" files exist in any user's home directory. Therefore, to use Procmail, each "
"user must construct a <filename>.procmailrc</filename> file with specific "
"environment variables and rules."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Whether Procmail acts upon an email message depends upon whether the message"
" matches a specified set of conditions or <firstterm>recipes</firstterm> in "
"the <filename>rc</filename> file. If a message matches a recipe, then the "
"email is placed in a specified file, is deleted, or is otherwise processed."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"When Procmail starts, it reads the email message and separates the body from"
" the header information. Next, Procmail looks for a "
"<filename>/etc/procmailrc</filename> file and <filename>rc</filename> files "
"in the <filename>/etc/procmailrcs</filename> directory for default, system-"
"wide, Procmail environmental variables and recipes. Procmail then searches "
"for a <filename>.procmailrc</filename> file in the user's home directory. "
"Many users also create additional <filename>rc</filename> files for Procmail"
" that are referred to within the <filename>.procmailrc</filename> file in "
"their home directory."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Procmail Configuration"
msgstr "Procmail 配置"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Procmail</primary> <secondary>configuration</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary> <filename>.procmailrc</filename> </primary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The Procmail configuration file contains important environmental variables. "
"These variables specify things such as which messages to sort and what to do"
" with the messages that do not match any recipes."
msgstr "Procmail 配置文件包含重要环境变量。这些变量指定一些规则，比如哪些信息需要分类以及对不符合任何方案的信息如何处理。"

#. Tag: para
#, no-c-format
msgid ""
"These environmental variables usually appear at the beginning of the "
"<filename>~/.procmailrc</filename> file in the following format:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"<replaceable>&lt;env-variable&gt;</replaceable>=\"<replaceable>&lt;value&gt;</replaceable>\"\n"
"      "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In this example, <command><replaceable>&lt;env-variable&gt;</replaceable> "
"</command> is the name of the variable and "
"<command><replaceable>&lt;value&gt;</replaceable> </command> defines the "
"variable."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"There are many environment variables not used by most Procmail users and "
"many of the more important environment variables are already defined by a "
"default value. Most of the time, the following variables are used:"
msgstr "有很多变量是大多数 Procmail 用户不需要的，而且很多更重要的环境变量已经定义了默认值。大多数情况下会使用以下变量："

#. Tag: para
#, no-c-format
msgid ""
"<command>DEFAULT</command> — Sets the default mailbox where messages that do"
" not match any recipes are placed."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The default <command>DEFAULT</command> value is the same as "
"<command>$ORGMAIL</command>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>INCLUDERC</command> — Specifies additional <filename>rc</filename> "
"files containing more recipes for messages to be checked against. This "
"breaks up the Procmail recipe lists into individual files that fulfill "
"different roles, such as blocking spam and managing email lists, that can "
"then be turned off or on by using comment characters in the user's "
"<filename>~/.procmailrc</filename> file."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For example, lines in a user's <filename>.procmailrc</filename> file may "
"look like this:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"MAILDIR=$HOME/Msgs INCLUDERC=$MAILDIR/lists.rc INCLUDERC=$MAILDIR/spam.rc"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To turn off Procmail filtering of email lists but leaving spam control in "
"place, comment out the first <command>INCLUDERC</command> line with a hash "
"sign (<command>#</command>)."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>LOCKSLEEP</command> — Sets the amount of time, in seconds, between "
"attempts by Procmail to use a particular lockfile. The default is "
"<constant>8</constant> seconds."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>LOCKTIMEOUT</command> — Sets the amount of time, in seconds, that "
"must pass after a lockfile was last modified before Procmail assumes that "
"the lockfile is old and can be deleted. The default is "
"<constant>1024</constant> seconds."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>LOGFILE</command> — The file to which any Procmail information or "
"error messages are written."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>MAILDIR</command> — Sets the current working directory for "
"Procmail. If set, all other Procmail paths are relative to this directory."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>ORGMAIL</command> — Specifies the original mailbox, or another "
"place to put the messages if they cannot be placed in the default or recipe-"
"required location."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"By default, a value of <command>/var/spool/mail/$LOGNAME</command> is used."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>SUSPEND</command> — Sets the amount of time, in seconds, that "
"Procmail pauses if a necessary resource, such as swap space, is not "
"available."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>SWITCHRC</command> — Allows a user to specify an external file "
"containing additional Procmail recipes, much like the "
"<command>INCLUDERC</command> option, except that recipe checking is actually"
" stopped on the referring configuration file and only the recipes on the "
"<command>SWITCHRC</command>-specified file are used."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>VERBOSE</command> — Causes Procmail to log more information. This "
"option is useful for debugging."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Other important environmental variables are pulled from the shell, such as "
"<command>LOGNAME</command>, which is the login name; "
"<command>HOME</command>, which is the location of the home directory; and "
"<command>SHELL</command>, which is the default shell."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A comprehensive explanation of all environments variables, as well as their "
"default values, is available in the <filename>procmailrc</filename> man "
"page."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Procmail Recipes"
msgstr "Procmail 方案"

#. Tag: indexterm
#, no-c-format
msgid "<primary>Procmail</primary> <secondary>recipes</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"New users often find the construction of recipes the most difficult part of "
"learning to use Procmail. To some extent, this is understandable, as recipes"
" do their message matching using <firstterm>regular expressions</firstterm>,"
" which is a particular format used to specify qualifications for a matching "
"string. However, regular expressions are not very difficult to construct and"
" even less difficult to understand when read. Additionally, the consistency "
"of the way Procmail recipes are written, regardless of regular expressions, "
"makes it easy to learn by example. To see example Procmail recipes, refer to"
" <xref linkend=\"s3-email-procmail-recipes-examples\" />."
msgstr ""

#. Tag: para
#, no-c-format
msgid "Procmail recipes take the following form:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
":0<replaceable>&lt;flags&gt;: &lt;lockfile-name&gt;</replaceable> * <replaceable>&lt;special-condition-character&gt;</replaceable>\n"
"        <replaceable>&lt;condition-1&gt;</replaceable> * <replaceable>&lt;special-condition-character&gt;</replaceable>\n"
"        <replaceable>&lt;condition-2&gt;</replaceable> * <replaceable>&lt;special-condition-character&gt;</replaceable>\n"
"        <replaceable>&lt;condition-N&gt;</replaceable>\n"
"        <replaceable>&lt;special-action-character&gt;</replaceable>\n"
"        <replaceable>&lt;action-to-perform&gt;</replaceable>\n"
"      "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The first two characters in a Procmail recipe are a colon and a zero. "
"Various flags can be placed after the zero to control how Procmail processes"
" the recipe. A colon after the "
"<command><replaceable>&lt;flags&gt;</replaceable> </command> section "
"specifies that a lockfile is created for this message. If a lockfile is "
"created, the name can be specified by replacing <command><replaceable>&lt"
";lockfile-name&gt;</replaceable> </command>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A recipe can contain several conditions to match against the message. If it "
"has no conditions, every message matches the recipe. Regular expressions are"
" placed in some conditions to facilitate message matching. If multiple "
"conditions are used, they must all match for the action to be performed. "
"Conditions are checked based on the flags set in the recipe's first line. "
"Optional special characters placed after the asterisk character "
"(<command>*</command>) can further control the condition."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The <command><replaceable>&lt;action-to-perform&gt;</replaceable></command> "
"argument specifies the action taken when the message matches one of the "
"conditions. There can only be one action per recipe. In many cases, the name"
" of a mailbox is used here to direct matching messages into that file, "
"effectively sorting the email. Special action characters may also be used "
"before the action is specified. Refer to <xref linkend=\"s3-email-procmail-"
"recipes-special\" /> for more information."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Delivering vs. Non-Delivering Recipes"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>recipes</secondary> "
"<tertiary>delivering</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>recipes</secondary> <tertiary>non-"
"delivering</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The action used if the recipe matches a particular message determines "
"whether it is considered a <firstterm>delivering</firstterm> or <firstterm"
">non-delivering</firstterm> recipe. A delivering recipe contains an action "
"that writes the message to a file, sends the message to another program, or "
"forwards the message to another email address. A non-delivering recipe "
"covers any other actions, such as a <firstterm>nesting block</firstterm>. A "
"nesting block is a set of actions, contained in braces <command>{</command> "
"<command>}</command>, that are performed on messages which match the "
"recipe's conditions. Nesting blocks can be nested inside one another, "
"providing greater control for identifying and performing actions on "
"messages."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"When messages match a delivering recipe, Procmail performs the specified "
"action and stops comparing the message against any other recipes. Messages "
"that match non-delivering recipes continue to be compared against other "
"recipes."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Flags"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>recipes</secondary> "
"<tertiary>flags</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Flags are essential to determine how or if a recipe's conditions are "
"compared to a message. The following flags are commonly used:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>A</command> — Specifies that this recipe is only used if the "
"previous recipe without an <command>A</command> or <command>a</command> flag"
" also matched this message."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>a</command> — Specifies that this recipe is only used if the "
"previous recipe with an <command>A</command> or <command>a</command> flag "
"also matched this message <emphasis>and</emphasis> was successfully "
"completed."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>B</command> — Parses the body of the message and looks for matching"
" conditions."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>b</command> — Uses the body in any resulting action, such as "
"writing the message to a file or forwarding it. This is the default "
"behavior."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>c</command> — Generates a carbon copy of the email. This is useful "
"with delivering recipes, since the required action can be performed on the "
"message and a copy of the message can continue being processed in the "
"<filename>rc</filename> files."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>D</command> — Makes the <command>egrep</command> comparison case-"
"sensitive. By default, the comparison process is not case-sensitive."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>E</command> — While similar to the <command>A</command> flag, the "
"conditions in the recipe are only compared to the message if the immediately"
" preceding the recipe without an <command>E</command> flag did not match. "
"This is comparable to an <wordasword>else</wordasword> action."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>e</command> — The recipe is compared to the message only if the "
"action specified in the immediately preceding recipe fails."
msgstr ""

#. Tag: para
#, no-c-format
msgid "<command>f</command> — Uses the pipe as a filter."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>H</command> — Parses the header of the message and looks for "
"matching conditions. This is the default behavior."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>h</command> — Uses the header in a resulting action. This is the "
"default behavior."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>w</command> — Tells Procmail to wait for the specified filter or "
"program to finish, and reports whether or not it was successful before "
"considering the message filtered."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>W</command> — Is identical to <command>w</command> except that "
"\"Program failure\" messages are suppressed."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For a detailed list of additional flags, refer to the "
"<filename>procmailrc</filename> man page."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Specifying a Local Lockfile"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>recipes</secondary> <tertiary>local "
"lockfiles</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Lockfiles are very useful with Procmail to ensure that more than one process"
" does not try to alter a message simultaneously. Specify a local lockfile by"
" placing a colon (<command>:</command>) after any flags on a recipe's first "
"line. This creates a local lockfile based on the destination file name plus "
"whatever has been set in the <command>LOCKEXT</command> global environment "
"variable."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Alternatively, specify the name of the local lockfile to be used with this "
"recipe after the colon."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Special Conditions and Actions"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>recipes</secondary> <tertiary>special"
" conditions</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>recipes</secondary> <tertiary>special"
" actions</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Special characters used before Procmail recipe conditions and actions change"
" the way they are interpreted."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The following characters may be used after the asterisk character "
"(<command>*</command>) at the beginning of a recipe's condition line:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>!</command> — In the condition line, this character inverts the "
"condition, causing a match to occur only if the condition does not match the"
" message."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>&lt;</command> — Checks if the message is under a specified number "
"of bytes."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>&gt;</command> — Checks if the message is over a specified number "
"of bytes."
msgstr ""

#. Tag: para
#, no-c-format
msgid "The following characters are used to perform special actions:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>!</command> — In the action line, this character tells Procmail to "
"forward the message to the specified email addresses."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>$</command> — Refers to a variable set earlier in the "
"<filename>rc</filename> file. This is often used to set a common mailbox "
"that is referred to by various recipes."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>|</command> — Starts a specified program to process the message."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<command>{</command> and <command>}</command> — Constructs a nesting block, "
"used to contain additional recipes to apply to matching messages."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"If no special character is used at the beginning of the action line, "
"Procmail assumes that the action line is specifying the mailbox in which to "
"write the message."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Recipe Examples"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>recipes</secondary> "
"<tertiary>examples</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Procmail is an extremely flexible program, but as a result of this "
"flexibility, composing Procmail recipes from scratch can be difficult for "
"new users."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The best way to develop the skills to build Procmail recipe conditions stems"
" from a strong understanding of regular expressions combined with looking at"
" many examples built by others. A thorough explanation of regular "
"expressions is beyond the scope of this section. The structure of Procmail "
"recipes and useful sample Procmail recipes can be found at various places on"
" the Internet (such as <ulink "
"url=\"http://www.iki.fi/era/procmail/links.html\">http://www.iki.fi/era/procmail/links.html</ulink>)."
" The proper use and adaptation of regular expressions can be derived by "
"viewing these recipe examples. In addition, introductory information about "
"basic regular expression rules can be found in the <filename>grep</filename>"
" man page."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The following simple examples demonstrate the basic structure of Procmail "
"recipes and can provide the foundation for more intricate constructions."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A basic recipe may not even contain conditions, as is illustrated in the "
"following example:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ":0: new-mail.spool"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The first line specifies that a local lockfile is to be created but does not"
" specify a name, so Procmail uses the destination file name and appends the "
"value specified in the <command>LOCKEXT</command> environment variable. No "
"condition is specified, so every message matches this recipe and is placed "
"in the single spool file called <filename>new-mail.spool</filename>, located"
" within the directory specified by the <command>MAILDIR</command> "
"environment variable. An MUA can then view messages in this file."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A basic recipe, such as this, can be placed at the end of all "
"<filename>rc</filename> files to direct messages to a default location."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The following example matched messages from a specific email address and "
"throws them away."
msgstr ""

#. Tag: screen
#, no-c-format
msgid ":0 * ^From: spammer@domain.com /dev/null"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"With this example, any messages sent by "
"<computeroutput>spammer@domain.com</computeroutput> are sent to the "
"<filename>/dev/null</filename> device, deleting them."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Be certain that rules are working as intended before sending messages to "
"<filename>/dev/null</filename> for permanent deletion. If a recipe "
"inadvertently catches unintended messages, and those messages disappear, it "
"becomes difficult to troubleshoot the rule."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"A better solution is to point the recipe's action to a special mailbox, "
"which can be checked from time to time to look for false positives. Once "
"satisfied that no messages are accidentally being matched, delete the "
"mailbox and direct the action to send the messages to "
"<filename>/dev/null</filename>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The following recipe grabs email sent from a particular mailing list and "
"places it in a specified folder."
msgstr ""

#. Tag: screen
#, no-c-format
msgid ":0: * ^(From|Cc|To).*tux-lug tuxlug"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Any messages sent from the <computeroutput>tux-"
"lug@domain.com</computeroutput> mailing list are placed in the "
"<filename>tuxlug</filename> mailbox automatically for the MUA. Note that the"
" condition in this example matches the message if it has the mailing list's "
"email address on the <computeroutput>From</computeroutput>, "
"<computeroutput>Cc</computeroutput>, or <computeroutput>To</computeroutput> "
"lines."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Consult the many Procmail online resources available in <xref linkend=\"s1"
"-email-additional-resources\" /> for more detailed and powerful recipes."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Spam Filters"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>recipes</secondary> "
"<tertiary>SpamAssassin</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>SpamAssassin</primary> <secondary>using with Procmail</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>spam</secondary> <tertiary>filtering "
"out</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Because it is called by Sendmail, Postfix, and Fetchmail upon receiving new "
"emails, Procmail can be used as a powerful tool for combating spam."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"This is particularly true when Procmail is used in conjunction with "
"SpamAssassin. When used together, these two applications can quickly "
"identify spam emails, and sort or destroy them."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"SpamAssassin uses header analysis, text analysis, blacklists, a spam-"
"tracking database, and self-learning Bayesian spam analysis to quickly and "
"accurately identify and tag spam."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Note: Installing the <package>spamassassin</package> package"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In order to use <application>SpamAssassin</application>, first ensure the "
"<package>spamassassin</package> package is installed on your system by "
"running, as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid "~]# <command>yum install spamassassin</command>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The easiest way for a local user to use SpamAssassin is to place the "
"following line near the top of the <filename>~/.procmailrc</filename> file:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"<command>INCLUDERC=/etc/mail/spamassassin/spamassassin-default.rc</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The <filename>/etc/mail/spamassassin/spamassassin-default.rc</filename> "
"contains a simple Procmail rule that activates SpamAssassin for all incoming"
" email. If an email is determined to be spam, it is tagged in the header as "
"such and the title is prepended with the following pattern:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid "*****SPAM*****"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The message body of the email is also prepended with a running tally of what"
" elements caused it to be diagnosed as spam."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To file email tagged as spam, a rule similar to the following can be used:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"<command>:0 Hw * ^X-Spam-Status: Yes spam</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"This rule files all email tagged in the header as spam into a mailbox called"
" <filename>spam</filename>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Since SpamAssassin is a Perl script, it may be necessary on busy servers to "
"use the binary SpamAssassin daemon (<systemitem "
"class=\"daemon\">spamd</systemitem>) and the client application "
"(<application>spamc</application>). Configuring SpamAssassin this way, "
"however, requires root access to the host."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To start the <systemitem class=\"daemon\">spamd</systemitem> daemon, type "
"the following command:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"~]# <command>service spamassassin start</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To start the SpamAssassin daemon when the system is booted, use an "
"initscript utility, such as the <application>Services Configuration "
"Tool</application> (<command>system-config-services</command>), to turn on "
"the <computeroutput>spamassassin</computeroutput> service. Refer to <xref "
"linkend=\"ch-Controlling_Access_to_Services\" /> for more information about "
"starting and stopping services."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To configure Procmail to use the SpamAssassin client application instead of "
"the Perl script, place the following line near the top of the "
"<filename>~/.procmailrc</filename> file. For a system-wide configuration, "
"place it in <filename>/etc/procmailrc</filename>:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"<command>INCLUDERC=/etc/mail/spamassassin/spamassassin-spamc.rc</command>\n"
"        "
msgstr ""

#. Tag: title
#, no-c-format
msgid "Mail User Agents"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"&MAJOROS; offers a variety of email programs, both, graphical email client "
"programs, such as <application>Evolution</application>, and text-based email"
" programs such as <command>mutt</command>."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The remainder of this section focuses on securing communication between a "
"client and a server."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Securing Communication"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Popular MUAs included with &MAJOROS;, such as "
"<application>Evolution</application> and <command>mutt</command> offer SSL-"
"encrypted email sessions."
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary>email</primary> <secondary>security</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Like any other service that flows over a network unencrypted, important "
"email information, such as usernames, passwords, and entire messages, may be"
" intercepted and viewed by users on the network. Additionally, since the "
"standard <systemitem class=\"protocol\">POP</systemitem> and <systemitem "
"class=\"protocol\">IMAP</systemitem> protocols pass authentication "
"information unencrypted, it is possible for an attacker to gain access to "
"user accounts by collecting usernames and passwords as they are passed over "
"the network."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Secure Email Clients"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>security</secondary> "
"<tertiary>clients</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Most Linux MUAs designed to check email on remote servers support SSL "
"encryption. To use SSL when retrieving email, it must be enabled on both the"
" email client and the server."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"SSL is easy to enable on the client-side, often done with the click of a "
"button in the MUA's configuration window or via an option in the MUA's "
"configuration file. Secure <systemitem class=\"protocol\">IMAP</systemitem> "
"and <systemitem class=\"protocol\">POP</systemitem> have known port numbers "
"(<constant>993</constant> and <constant>995</constant>, respectively) that "
"the MUA uses to authenticate and download messages."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Securing Email Client Communications"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>security</secondary> "
"<tertiary>servers</tertiary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid "<primary> <command>stunnel</command> </primary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Offering SSL encryption to <systemitem class=\"protocol\">IMAP</systemitem> "
"and <systemitem class=\"protocol\">POP</systemitem> users on the email "
"server is a simple matter."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"First, create an SSL certificate. This can be done in two ways: by applying "
"to a <firstterm>Certificate Authority</firstterm> "
"(<firstterm>CA</firstterm>) for an SSL certificate or by creating a self-"
"signed certificate."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Self-signed certificates should be used for testing purposes only. Any "
"server used in a production environment should use an SSL certificate "
"granted by a CA."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To create a self-signed SSL certificate for <systemitem "
"class=\"protocol\">IMAP</systemitem> or <systemitem "
"class=\"protocol\">POP</systemitem>, change to the "
"<filename>/etc/pki/dovecot/</filename> directory, edit the certificate "
"parameters in the <filename>/etc/pki/dovecot/dovecot-openssl.conf</filename>"
" configuration file as you prefer, and type the following commands, as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"dovecot]# <command>rm -f certs/dovecot.pem private/dovecot.pem</command>\n"
"dovecot]# <command>/usr/libexec/dovecot/mkcert.sh</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Once finished, make sure you have the following configurations in your "
"<filename>/etc/dovecot/conf.d/10-ssl.conf</filename> file:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"\n"
"ssl_cert = &lt;/etc/pki/dovecot/certs/dovecot.pem\n"
"ssl_key = &lt;/etc/pki/dovecot/private/dovecot.pem\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Execute the <command>service dovecot restart</command> command to restart "
"the <command>dovecot</command> daemon."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Alternatively, the <command>stunnel</command> command can be used as an SSL "
"encryption wrapper around the standard, non-secure connections to "
"<systemitem class=\"protocol\">IMAP</systemitem> or <systemitem "
"class=\"protocol\">POP</systemitem> services."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The <command>stunnel</command> utility uses external OpenSSL libraries "
"included with &MAJOROS; to provide strong cryptography and to protect the "
"network connections. It is recommended to apply to a CA to obtain an SSL "
"certificate, but it is also possible to create a self-signed certificate."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Note: Installing the <package>stunnel</package> package"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In order to use <command>stunnel</command>, first ensure the "
"<package>stunnel</package> package is installed on your system by running, "
"as root:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid "~]# <command>yum install stunnel</command>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"To create a self-signed SSL certificate, change to the "
"<filename>/etc/pki/tls/certs/</filename> directory, and type the following "
"command:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"certs]# <command>make stunnel.pem</command>\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid "Answer all of the questions to complete the process."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Once the certificate is generated, create an <command>stunnel</command> "
"configuration file, for example <filename>/etc/stunnel/mail.conf</filename>,"
" with the following content:"
msgstr ""

#. Tag: screen
#, no-c-format
msgid ""
"cert = /etc/pki/tls/certs/stunnel.pem\n"
"\n"
"[pop3s]\n"
"accept  = 995\n"
"connect = 110\n"
"\n"
"[imaps]\n"
"accept  = 993\n"
"connect = 143\n"
"        "
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Once you start <command>stunnel</command> with the created configuration "
"file using the <command>/usr/bin/stunnel /etc/stunnel/mail.conf</command> "
"command, it will be possible to use an <systemitem "
"class=\"protocol\">IMAP</systemitem> or a <systemitem "
"class=\"protocol\">POP</systemitem> email client and connect to the email "
"server using SSL encryption."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"For more information on <command>stunnel</command>, refer to the "
"<command>stunnel</command> man page or the documents in the "
"<filename>/usr/share/doc/stunnel-<replaceable>&lt;version-"
"number&gt;</replaceable> </filename>/ directory, where <replaceable>&lt"
";version-number&gt;</replaceable> is the version number of "
"<command>stunnel</command>."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Additional Resources"
msgstr "其它资料"

#. Tag: indexterm
#, no-c-format
msgid "<primary>email</primary> <secondary>additional resources</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Sendmail</primary> <secondary>additional resources</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Procmail</primary> <secondary>additional resources</secondary>"
msgstr ""

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>Fetchmail</primary> <secondary>additional resources</secondary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"The following is a list of additional documentation about email "
"applications."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Installed Documentation"
msgstr "安装了的文档"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>additional resources</secondary> "
"<tertiary>installed documentation</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"Information on configuring Sendmail is included with the "
"<filename>sendmail</filename> and <filename>sendmail-cf</filename> packages."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>/usr/share/sendmail-cf/README</filename> — Contains information on"
" the <command>m4</command> macro processor, file locations for Sendmail, "
"supported mailers, how to access enhanced features, and more."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"In addition, the <filename>sendmail</filename> and "
"<filename>aliases</filename> man pages contain helpful information covering "
"various Sendmail options and the proper configuration of the Sendmail "
"<filename>/etc/mail/aliases</filename> file."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>/usr/share/doc/postfix-<replaceable>&lt;version-"
"number&gt;</replaceable> </filename> — Contains a large amount of "
"information about ways to configure Postfix. Replace <replaceable>&lt"
";version-number&gt;</replaceable> with the version number of Postfix."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>/usr/share/doc/fetchmail-<replaceable>&lt;version-"
"number&gt;</replaceable> </filename> — Contains a full list of Fetchmail "
"features in the <filename>FEATURES</filename> file and an introductory "
"<filename>FAQ</filename> document. Replace <replaceable>&lt;version-"
"number&gt;</replaceable> with the version number of Fetchmail."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>/usr/share/doc/procmail-<replaceable>&lt;version-"
"number&gt;</replaceable> </filename> — Contains a "
"<filename>README</filename> file that provides an overview of Procmail, a "
"<filename>FEATURES</filename> file that explores every program feature, and "
"an <filename>FAQ</filename> file with answers to many common configuration "
"questions. Replace <replaceable>&lt;version-number&gt;</replaceable> with "
"the version number of Procmail."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"When learning how Procmail works and creating new recipes, the following "
"Procmail man pages are invaluable:"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>procmail</filename> — Provides an overview of how Procmail works "
"and the steps involved with filtering email."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>procmailrc</filename> — Explains the <filename>rc</filename> file "
"format used to construct recipes."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>procmailex</filename> — Gives a number of useful, real-world "
"examples of Procmail recipes."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>procmailsc</filename> — Explains the weighted scoring technique "
"used by Procmail to match a particular recipe to a message."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<filename>/usr/share/doc/spamassassin-<replaceable>&lt;version-"
"number&gt;</replaceable>/</filename> — Contains a large amount of "
"information pertaining to SpamAssassin. Replace <replaceable>&lt;version-"
"number&gt;</replaceable> with the version number of the "
"<filename>spamassassin</filename> package."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Useful Websites"
msgstr "有用的网站"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>additional resources</secondary> "
"<tertiary>useful websites</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<ulink url=\"http://www.sendmail.org/\">http://www.sendmail.org/</ulink> — "
"Offers a thorough technical breakdown of Sendmail features, documentation "
"and configuration examples."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<ulink url=\"http://www.sendmail.com/\">http://www.sendmail.com/</ulink> — "
"Contains news, interviews and articles concerning Sendmail, including an "
"expanded view of the many options available."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<ulink url=\"http://www.postfix.org/\">http://www.postfix.org/</ulink> — The"
" Postfix project home page contains a wealth of information about Postfix. "
"The mailing list is a particularly good place to look for information."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<ulink "
"url=\"http://fetchmail.berlios.de/\">http://fetchmail.berlios.de/</ulink> — "
"The home page for Fetchmail, featuring an online manual, and a thorough FAQ."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<ulink url=\"http://www.procmail.org/\">http://www.procmail.org/</ulink> — "
"The home page for Procmail with links to assorted mailing lists dedicated to"
" Procmail as well as various FAQ documents."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<ulink url=\"http://partmaps.org/era/procmail/mini-"
"faq.html\">http://partmaps.org/era/procmail/mini-faq.html</ulink> — An "
"excellent Procmail FAQ, offers troubleshooting tips, details about file "
"locking, and the use of wildcard characters."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<ulink "
"url=\"http://www.uwasa.fi/~ts/info/proctips.html\">http://www.uwasa.fi/~ts/info/proctips.html</ulink>"
" — Contains dozens of tips that make using Procmail much easier. Includes "
"instructions on how to test <filename>.procmailrc</filename> files and use "
"Procmail scoring to decide if a particular action should be taken."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<ulink "
"url=\"http://www.spamassassin.org/\">http://www.spamassassin.org/</ulink> — "
"The official site of the SpamAssassin project."
msgstr ""

#. Tag: title
#, no-c-format
msgid "Related Books"
msgstr "相关书籍"

#. Tag: indexterm
#, no-c-format
msgid ""
"<primary>email</primary> <secondary>additional resources</secondary> "
"<tertiary>related books</tertiary>"
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<citetitle>Sendmail Milters: A Guide for Fighting Spam</citetitle> by Bryan "
"Costales and Marcia Flynt; Addison-Wesley — A good Sendmail guide that can "
"help you customise your mail filters."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<citetitle>Sendmail</citetitle> by Bryan Costales with Eric Allman et al; "
"O'Reilly &amp; Associates — A good Sendmail reference written with the "
"assistance of the original creator of Delivermail and Sendmail."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<citetitle>Removing the Spam: Email Processing and Filtering</citetitle> by "
"Geoff Mulligan; Addison-Wesley Publishing Company — A volume that looks at "
"various methods used by email administrators using established tools, such "
"as Sendmail and Procmail, to manage spam problems."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<citetitle>Internet Email Protocols: A Developer's Guide</citetitle> by "
"Kevin Johnson; Addison-Wesley Publishing Company — Provides a very thorough "
"review of major email protocols and the security they provide."
msgstr ""

#. Tag: para
#, no-c-format
msgid ""
"<citetitle>Managing IMAP</citetitle> by Dianna Mullet and Kevin Mullet; "
"O'Reilly &amp; Associates — Details the steps required to configure an IMAP "
"server."
msgstr ""