How to send e-mail from cron only in special circumstances

memorum · 09-22-2014, 06:14 AM

Hi!
I wrote very simple bash script, which runs every hour and just restart some service. No every time I receive output of those commands through e-mail. I would like to receive it only in case of errors or something unusual.

The first idea was to run commands twice and compare for differences (but it's to much work, it can differ slightly). The second was to redirect output to /dev/null, and send through e-mail only error stream (how to do it?). The third is to check result (ok - result==0), and mail only when result is other than that.

Any ideas?

nisagnel · 09-22-2014, 07:26 AM

Hi,

I hope this will help you.after running any command,get the status of the command ran(success or fail).

for example:
service http restart
exit_status=$?

#### now check the status using if condition,if it not ran successfully mail to the user ##
if [ "$exit_status" -ne 0 ]
then
echo "command not successfull"
mail -s "http restart info" yourname@mail.com
else
echo "command was success"
fi

memorum · 09-22-2014, 09:26 AM

Cron automatically send output of command to me, therefore it's useless to use `mail`.
But your post was inspiration for me, so I made script:

Code:

#!/bin/sh
output=$(some_command)
output1=$(some_command)
output2=$(/usr/sbin/service nginx reload)
exit_status=$?
if [ "$exit_status" -ne 0 ]; then
echo "error in reload, check it"
echo $output
echo $output1
echo $output2
fi

I need to test it, but I hope I'm close to achieve my goal.
If you have some remarks, write it!