Shell Script to Check Service Status

In this tutorial, I will explain a shell script that check if service is running and if it is not then will try to start it.

Its good for system admin to make sure the crucial services are running all the time.

Shell Script to check service status

This script will check the status of any init.d service and start that service if it is not running.

#!/bin/bash

if [ "$#" = 0 ]

then
echo "Usage $0 "

exit 1

fi

service=$1

is_running=`ps aux | grep -v grep| grep -v "$0" | grep $service| wc -l | awk '{print $1}'`

if [ $is_running != "0" ] ;

then

echo "Service $service is running"

else

echo

initd=`ls /etc/init.d/ | grep $service | wc -l | awk '{ print $1 }'`

if [ $initd = "1" ];

then
startup=`ls /etc/init.d/ | grep $service`

echo -n "Found startap script /etc/init.d/${startup}. Start it? Y/n ? "

read answer

if [ $answer = "y" -o $answer = "Y" ];

then
echo "Starting service..."

/etc/init.d/${startup} start

fi

fi

fi

Results

bobbin@linoxide:/$ ./service.sh apparmor
Service apparmor is not running
Found startap script /etc/init.d/apparmor. Start it? Y/n ? Y
Starting service...
* Starting AppArmor profiles [OK]

Learn this Script Line By Line

#check if service name passed to script as argument, if there no arguments (0) do next

if [ "$#" = 0 ]

then

"Usage $0 " #write to terminal usage

echo

#since no arguments – we need to exit script and user re-run it

exit 1

fi

#get service name from first argument

service=$1

#this check ,if service running using ps command, after we remove our process from the output, since script will also match, with wc we count number of matching lines.

is_running=`ps aux | grep -v grep| grep -v "$0" | grep $service| wc -l | awk '{print $1}'`

#is number of lines are not 0 do next

if [ $is_running != "0" ] ;

then

#just put this line to terminal

echo "Service $service is running"

#if number of precesses is 0

else

#Service $service is not running" #just put this string to terminal

echo

#checking for files in /etc/init.d
(directory with start-up scripts) with name similar to service

initd=`ls /etc/init.d/ | grep $service | wc -l | awk '{ print $1 }'`

#if there is script with similar name

if [ $initd = "1" ];

then

#this line get name of startup script (ls - lists files in directory

startup=`ls /etc/init.d/ | grep $service`

echo -n "Found startap script /etc/init.d/${startup}. Start it? Y/n ? "

#waiting for user answer

read answer

#if answer Y or y

if [ $answer = "y" -o $answer = "Y" ];

then
echo "Starting service..."

#running startup script

/etc/init.d/${startup} start

fi
#exit of if loop

fi

#exit of if loop

fi