Monitoring memcached

You could run a cronjob to monitor your memcache process. On my personal account, I run the following script via cron. I am not using a socket, but this should still work.

#!/bin/bash

if ps -u username |grep -E 'memcached$' > /dev/null
then
  echo "memcached is running."
else
  echo "starting memcache."
  /usr/bin/memcached -d -m 256 -s $HOME/memcached.sock -P $HOME/memcached.pid
fi

Then my cronjob is set up like this:

*/5 * * * * cd ~/scripts;./memcached_check.sh > /dev/null 2>&1

This will run your script every 5 minutes to check if memcache is running and restart it if it is not.

You could also add to the script to send an email depending on the status.

As for why it would have been shutdown, it could have been that the server was restarted and there is no process to restart your memcached process. Or, in some cases, the processes could have been killed because your processes have gone over your account's memory limit.

Hope that helps.