以下是自己收集的实用Linux下简单配置外部邮箱发送邮件的方法：

1、配置/etc/mail.rc，使用mail命令

# vim /etc/mail.rc

###调用外部邮箱   
set from=test@qqextend.com     
set smtp=smtp.exmail.qq.com  
set smtp-auth-user=test@qqextend.com     
set smtp-auth-password="XXXXXX"

set smtp-auth=login

然后使用mail命令即可发送邮件了

2、msmtp+mutt方式

msmtp下载地址：https://sourceforge.net/projects/msmtp/files/msmtp/

1）安装msmtp

# wget http://heanet.dl.sourceforge.net/project/msmtp/msmtp/1.6.5/msmtp-1.6.5.tar.xz

# xz -d msmtp-1.6.5.tar.xz

# tar xvf msmtp-1.6.5.tar

# cd msmtp-1.6.5

# ./configure --prefix=/usr/local/msmtp

# make && make install

2）配置msmtp

# vim ~/.msmtprc                                       
account default     
host smtp.exmail.qq.com     
from test@qqextend.com

user test@qqextend.com

password XXXXXX

auth login   
logfile ~/.msmtp.log

3）安装配置mutt

# yum install mutt -y

# vim /etc/Muttrc

set sendmail="/usr/local/msmtp/bin/msmtp"   
set use_from=yes     
set realname="XXXXXX"     
set editor="vim"

4）发送邮件

# echo "这里是正文" |mutt -s "这里是标题" my@163.com

5）报错排查

echo "Email" |mutt -s"test" XXX@sina.com

msmtp: envelope from address root@ not accepted by the server

msmtp: server message: 501 mail from address must be same as authorization user

msmtp: could not send mail (account default from /usr/local/msmtp/etc/msmtprc)

Error sending message, child exited 65 (Data format error.).

Could not send the message.

修改/etc/Muttrc：

set sendmail="/usr/local/msmtp/bin/msmtp"

set use_from=yes

set envelope_from="yes"

set realname="test@qqextend.com"

set editor="vim"

set from="test@qqextend.com"