SHELL SCRIPT TIPS: mailx function in linux

As linux server administrators we may have to send mails via command line. Especially, while writing a shell script to monitor something in server ( example load) and send out mails, mailx play an important role in this scenario.

Lets see how to install mailx function in a linux machine:
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root@newserver [~]# yum list | grep mailx
mailx.x86_64                               12.4-7.el6                  base
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The above command will show the available mailx package.

Use yum install to install mailx as below:
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yum install mailx
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Now, if you want to see the binary:
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 root@newserver [~]# which mailx
/bin/mailx
root@newserver [~]#
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So, if you roll out a script to many servers to send out mails using puppet, then it is always good to state a condition in your shells script as follows:

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if [ ! -f /bin/mailx ]; then
  echo "installing mailx";
  yum install mailx
fi
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The above condition will install mailx, if it does not exist.