Linux简单配置SendMail发送邮件

本文简单整理了一下如何在Linux服务器上安装、配置SendMail发送邮件的步骤，此文不是配置邮件服务器，具体测试环境为CentOS Linux release 7.2.1511 (Core) ，如遇特殊平台有所差别，请以实际情况为准则。

Linux 系统版本查看

 

检查、了解系统版本信息，主要是如果使用rpm安装时，需要下载合适的版本。

[root@mylnx06 ~]# more /etc/redhat-release
CentOS Linux release 7.2.1511 (Core)

 

检查是否安装sendmail组件

 

如下所示，该服务器上并没有安装sendmail的相关组件。那么我们直接使用yum安装sendmail组件即可。

[root@mylnx06 ~]# rpm -qa | grep sendmail



[root@mylnx06 ~]# yum list sendmail
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * epel: ftp.cuhk.edu.hk
Available Packages
sendmail.x86_64                                       8.14.7-4.el7                    base

 

使用yum安装sendmail组件，当然你可以使用其它方式安装，此处不做展开介绍。

[root@mylnx06 ~]# yum install sendmail.x86_64
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * epel: ftp.cuhk.edu.hk
Resolving Dependencies
--> Running transaction check
---> Package sendmail.x86_64 0:8.14.7-4.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

========================================================================================================================
 Package                     Arch                      Version                            Repository               Size
========================================================================================================================
Installing:
 sendmail                    x86_64                    8.14.7-4.el7                       base                    722 k

Transaction Summary
========================================================================================================================
Install  1 Package

Total download size: 722 k
Installed size: 1.6 M
Is this ok [y/d/N]: y
Downloading packages:
sendmail-8.14.7-4.el7.x86_64.rpm                                                                 | 722 kB  00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : sendmail-8.14.7-4.el7.x86_64                                                                         1/1
  Verifying  : sendmail-8.14.7-4.el7.x86_64                                                                         1/1

Installed:
  sendmail.x86_64 0:8.14.7-4.el7

Complete!
[root@mylnx06 ~]#

 

编辑/etc/aliases文件

 

Sendmail有一个非常实用的功能,就是为每个账号取别名(Aliase) 会使用一个在 /etc/aliases 中的档案做使用者名称转换的动作。 所以这个配置文件是可配也可以不配，具体视你的需求而定。

[root@mylnx06 ~]# vi /etc/aliases
#
#  Aliases in this file will NOT be expanded in the header from
#  Mail, but WILL be visible over networks or from /bin/mail.
#
#       >>>>>>>>>>      The program "newaliases" must be run after
#       >> NOTE >>      this file is updated for any changes to
#       >>>>>>>>>>      show through to sendmail.
#

# Basic system aliases -- these MUST be present.
mailer-daemon:  postmaster
postmaster:     root

# General redirections for pseudo accounts.
bin:            root
daemon:         root
adm:            root
lp:             root
sync:           root
shutdown:       root
halt:           root
mail:           root
news:           root
uucp:           root
operator:       root
games:          root
gopher:         root
ftp:            root
nobody:         root
radiusd:        root
nut:            root
dbus:           root
vcsa:           root
canna:          root
wnn:            root
rpm:            root
nscd:           root
pcap:           root
apache:         root
webalizer:      root
dovecot:        root
fax:            root
quagga:         root
radvd:          root
pvm:            root
amandabackup:           root
privoxy:        root
ident:          root
named:          root
xfs:            root
gdm:            root
mailnull:       root
postgres:       root
sshd:           root
smmsp:          root
postfix:        root
netdump:        root
ldap:           root
squid:          root
ntp:            root
mysql:          root
desktop:        root
rpcuser:        root
rpc:            root
nfsnobody:      root

ingres:         root
system:         root
toor:           root
manager:        root
dumper:         root
abuse:          root

newsadm:        news
newsadmin:      news
usenet:         news
ftpadm:         ftp
ftpadmin:       ftp
ftp-adm:        ftp
ftp-admin:      ftp
www:            webmaster
webmaster:      root
noc:            root
security:       root
hostmaster:     root
info:           postmaster
marketing:      postmaster
sales:          postmaster
support:        postmaster


# trap decode to catch security attacks
decode:         root

# Person who should get root's mail
#root:          marc

 

如下截图所示，如果我配置别名为root的，配置接收邮件（下面邮件仅仅是一个模板而已）

 

修改配置文件sendmail.cf

 

修改/etc/mail/sendmail.cf 添加对应的DS, DS后面为邮件服务器的IP地址。根据实际具体情况配置。其实这个配置文件，如果需要，还有蛮多需要配置、细化的地方，此处只讲述最简单的配置。

# host/domain names ending with a token in class P are canonical
CP.

# "Smart" relay host (may be null)
DS[xxx.xxx.xxx.xxx]


# operators that cannot be in local usernames (i.e., network indicators)
CO @ % !

# a class with just dot (for identifying canonical names)

 

重启sendmail服务

[root@mylnx06 ~]# service sendmail status
Redirecting to /bin/systemctl status  sendmail.service
● sendmail.service - Sendmail Mail Transport Agent
   Loaded: loaded (/usr/lib/systemd/system/sendmail.service; enabled; vendor preset: disabled)
   Active: inactive (dead)

Feb 22 10:29:45 azlnx06 systemd[1]: Stopped Sendmail Mail Transport Agent.


[root@mylnx06 ~]# service sendmail start
Redirecting to /bin/systemctl start  sendmail.service
[root@mylnx06 ~]# service sendmail status
Redirecting to /bin/systemctl status  sendmail.service
● sendmail.service - Sendmail Mail Transport Agent
   Loaded: loaded (/usr/lib/systemd/system/sendmail.service; enabled; vendor preset: disabled)
   Active: active (running) since Wed 2017-02-22 10:42:02 HKT; 5s ago
  Process: 46129 ExecStart=/usr/sbin/sendmail -bd $SENDMAIL_OPTS $SENDMAIL_OPTARG (code=exited, status=0/SUCCESS)
  Process: 46116 ExecStartPre=/etc/mail/make aliases (code=exited, status=0/SUCCESS)
  Process: 46115 ExecStartPre=/etc/mail/make (code=exited, status=0/SUCCESS)
 Main PID: 46131 (sendmail)
   CGroup: /system.slice/sendmail.service
           └─46131 sendmail: accepting connections

Feb 22 10:42:02 azlnx06 systemd[1]: Starting Sendmail Mail Transport Agent...
Feb 22 10:42:02 azlnx06 sendmail[46124]: alias database /etc/aliases rebuilt by root
Feb 22 10:42:02 azlnx06 sendmail[46124]: /etc/aliases: 77 aliases, longest 17 bytes, 792 bytes total
Feb 22 10:42:02 azlnx06 sendmail[46131]: starting daemon (8.14.7): SMTP+queueing@01:00:00
Feb 22 10:42:02 azlnx06 systemd[1]: PID file /run/sendmail.pid not readable (yet?) after start.
Feb 22 10:42:02 azlnx06 systemd[1]: Started Sendmail Mail Transport Agent

 

测试邮件服务

 

如下所示，使用mail命令测试能否成功收到邮件。如果成功，表示前面配置OK， 如果没有收到邮件，则必须检查日志，然后根据具体错误信息诊断问题。

[root@mylnx06 ~]# cat > test.txt
it is only test
^Z
[1]+  Stopped                 cat > test.txt
[root@mylnx06 ~]# mail -s "test" konglb@xxxx.com < test.txt
[root@mylnx06 ~]#


[azrlnx06azlnx06 ~]$ echo 'it is only a test' | mail -s "test eamil"  konglb@xxxx.com
[azrlnx06@azlnx06 ~]$