linux script to check if a service is running and start it, if it’s stopped

 
#!/bin/bash
service=replace_me_with_a_valid_service
if (( $(ps -ef | grep -v grep | grep $service | wc -l) > 0 ))
then
echo "$service is running!!!"
else
/etc/init.d/$service start
fi

From: http://www.akamaras.com/linux/linux-script-to-check-if-a-service-is-running-and-start-it-if-its-stopped/