Shell Script To Monitor Services Such As Web / Http, Ssh, Mail Server

in Monitoring last updated July 14, 2009

#!/bin/bash
# Shell script to monitor running services such as web/http, ssh, mail etc. 
# If service fails it will send an Email to ADMIN user
# -------------------------------------------------------------------------
# Copyright (c) 2006 nixCraft project <http://www.cyberciti.biz/fb/>
# This script is licensed under GNU GPL version 2.0 or above
# -------------------------------------------------------------------------
# This script is part of nixCraft shell script collection (NSSC)
# Visit http://bash.cyberciti.biz/ for more information.
# ----------------------------------------------------------------------
# See URL for more info
# https://www.cyberciti.biz/tips/processing-the-delimited-files-using-cut-and-awk.html
# ---------------------------------------------------
# Last updated: Jun - 15 - 2009.
ports="22 53 80 25"
 
# service names as per above ports
service="SSH DNS WEB MAIL"
 
#Email id to send alert
ADMINEMAIL="admin@myispname.com"
 
#Bin paths, set them according to your Linux distro 
NETSTAT=/bin/netstat
MAIL=/usr/bin/mail
LOGGER=/usr/bin/logger
ID=/usr/bin/id
 
# Red hat usr uncomment 
MAIL=/bin/mail
LOGGER=/bin/logger
 
 
#Counters, set defaults
c=1
status=""
sendmail=0
 
# set the following to 1, if you want message in /var/log/messages via a SYSLOG
logtosyslog=0
 
# Log file used to send an email
LOG="/tmp/services.log.$$"
 
# log message to screen and a log file
log(){
	echo "$@"
	echo "$@" >> $LOG
}
 
# log message and stop script
die(){
	echo "$@"
	exit 999
}
 
# Make sure only root can run it
is_root(){
	local id=$($ID -u)
	[ $id -ne 0 ]  && die "You must be root to run $0."
}
# Look out for all bins and create a log file
init_script(){
	[ ! -x $MAIL ] && die "$MAIL command not found."
	[ ! -x $NETSTAT ] && die "$NETSTAT command not found."
	[ ! -x $LOGGER ] && die "$LOGGER command not found."
	[ ! -x $ID ] && die "$ID command not found."
	is_root
	>$LOG
}
 
 
# check for all running services and shoot an email if service is not running
chk_services(){
	log "-------------------------------------------------------------"
	log "Running services status @ $(hostname) [ $(date) ]"
	log "-------------------------------------------------------------"
 
	# get open ports 
	RPORTS=$($NETSTAT -tulpn -A inet | grep -vE '^Active|Proto' | grep 'LISTEN' | awk '{ print $4}' | cut -d: -f2 | sed '/^$/d' | sort  -u)
 
	# okay let us compare them
	for t in $ports
	do
		sname=$(echo $service | cut -d' ' -f$c)
		echo -en " $sname\t\t\t : "
		echo -en " $sname\t\t\t : " >> $LOG
		for r in $RPORTS
		do
			if [ "$r" == "$t" ]
			then
				status="YES"	
				sendmail=1
				break
			fi
		done
		echo -n "$status"
		echo ""
		echo -n "$status" >>$LOG
		echo "" >>$LOG
		# Log to a syslog /var/log/messages?
		# This is useful if you have a dedicated syslog server
		[ $logtosyslog -eq 1  ] && $LOGGER "$sname service running : $status"
 
		# Update counters for next round
		c=$( expr $c + 1 )
		status="NO"
	done
	log "-------------------------------------------------------------"
	log "This is an automatically generated $(uname) service status notification by $0 script."
 
	if [ $sendmail -eq 1 ];
	then
		$MAIL -s "Service Down @ $(hostname)" $ADMINEMAIL < $LOG
	fi
}
 
### main ###
init_script
chk_services
 
### remove a log file ###
[ -f $LOG ] && /bin/rm -f $LOG

Tagged as: adminemail, delimited, delimiter, echo line, echo service, expr, for loop, grep, loop method, mail service, mail services, monitor mail server, monitore web server, script collection, sendmail, service names, service status, shell loops, sudo, web mail, while loop

33 comment

Amar says:

September 11, 2012 at 3:13 am

Will this work to check for any webservices exposed by a server.
Amar says:

September 11, 2012 at 3:11 am

Hi,

Can we check through shell script if certain web service are up or not ?

Regards,
Amar Sharma
Michael Pivonka says:

April 12, 2012 at 7:36 am
Had problem with httpd not using a set ip and with the command in script above does not find services that don’t have them attached to an ip. So I have fixed this with the following command.
```
NETSTAT -tulpn | grep -vE '^Active|Proto' | grep 'LISTEN' | awk '{ print $4}' | awk -F: '{print $NF}' | sed '/^$/d' | sort -u
```
Aneesh says:

July 12, 2011 at 5:31 pm

On .el5 this is not working . Only SMTP status printed properly.
MuaDDip says:

October 17, 2010 at 7:26 am

RPORTS=$($NETSTAT -tulpn | grep -vE ‘^Active|Proto’ | grep ‘LISTEN’ | awk ‘{ print $4}’ | sed ‘s/[0-9a-z\.\:]*\:$[0-9]\+$$/\1/’ | sort -u)
Brian says:

October 10, 2010 at 4:33 pm

Hi,
You have a couple of bugs.
1. The script sends whenever at least one process is UP, you want the opposite.
2 You need to set status to ‘NO’ at the beginning of the loop rather than the end, otherwise if the first service is down it will have a status of empty string.
3. I would recommend using variables more descriptive than a single character, it will make it easier to read.

Here are the changes you need to make (note that I renamed the c variable to ‘count’):

# okay let us compare them
for t in $ports
do
status=”NO”
sname=$(echo $service | cut -d’ ‘ -f$count)
echo -en ” $sname\t\t\t : ”
echo -en ” $sname\t\t\t : ” >> $LOG
for r in $RPORTS
do
if [ “$r” == “$t” ]
then
status=”YES”
break
fi
done
if [ “$status” == “NO” ]
then
sendmail=1
fi
echo -n “$status”
echo “”
echo -n “$status” >>$LOG
echo “” >>$LOG
# Log to a syslog /var/log/messages?
# This is useful if you have a dedicated syslog server
[ $logtosyslog -eq 1 ] && $LOGGER “$sname service running : $status”

# Update counters for next round
count=$( expr $count + 1 )
done
1. Brian says:
  
  October 10, 2010 at 4:35 pm
  
  Whoops forgot to use the code blocks
  
  # okay let us compare them for t in $ports do status="NO" sname=$(echo $service | cut -d' ' -f$count) echo -en " $sname\t\t\t : " echo -en " $sname\t\t\t : " >> $LOG for r in $RPORTS do if [ "$r" == "$t" ] then status="YES" break fi done if [ "$status" == "NO" ] then sendmail=1 fi echo -n "$status" echo "" echo -n "$status" >>$LOG echo "" >>$LOG # Log to a syslog /var/log/messages? # This is useful if you have a dedicated syslog server [ $logtosyslog -eq 1 ] && $LOGGER "$sname service running : $status"
  # Update counters for next round count=$( expr $count + 1 ) done
Shaiju says:

August 26, 2010 at 10:19 am

Hi Smeven,
Thanks a lot…its worked Fine…:)
We want ot chane #get open ports section to
RPORTS=$($NETSTAT -tulapn -A inet,inet6 | grep -vE ‘^Active|Proto’ | grep ‘LISTEN’ | awk ‘{ print $4}’ | cut -d: -f2,4 | cut -d: -f2 | sed ‘/^$/d’ | sort -u) .Then only it will works on Ipv6..

Regards,
Shaiju
smeven says:

July 14, 2010 at 3:18 pm

My experience is that if a port of a running service dosn’t show up in the netstat line, it’s because it’s not using the protocol inet, but inet6 istead.
try netstat -tulpn -A inet,inet6 , but the some modifications to the cut part of this line has to be done also.
cut -d: -f2 would fail because of the format of inet6 is different , try cut -d: -f2,4 | cut -d: -f2 instead.
Jesse says:

April 9, 2010 at 10:51 pm

It’s emailing me even when all services are up:

$ sudo ./monitor.sh
————————————————————-
Running services status @ sabresboard [ Fri Apr 9 18:50:43 EDT 2010 ]
————————————————————-
SSH : YES
WEB : YES
MAIL : YES
————————————————————-
This is an automatically generated Linux service status notification by ./monitor.sh script

Still sends me an email.
shaiju says:

March 22, 2010 at 7:12 am

Hi thanks for the script..
How to monitor a new port using the scrip.i want to monitor 8080,and i changed port in the ports=”22 53 80 8080″
when running the script it is showing that
SSH : YES
DNS : YES
WEB : YES
tomcat : NO
please help me
Regards
Shaiju
Naleen says:

November 18, 2009 at 7:45 pm

This script worked first time for me, no probs at all.
no modification needed apart from email address, very nice !!!!
Jonas Holmgren says:

October 7, 2009 at 11:03 am

Note that due to the SLQ Injection protection in this forum, the opening apostrophes were replaced with back-quotes. What you see on the screen is correct, but you can’t copy and paste it into your script.
1. Vivek Gite says:
  
  October 14, 2009 at 6:26 am
  
  You can always download script file.

Try with

RPORTS="`nmap -sT $(ifconfig | grep 'inet addr:' | grep -v '127.0.0.1' | cut -f2 -d: | awk '{ print $1}') 2>/dev/null | awk '/^[0-9]/ {print $1}' | cut -f1 -d/`"

Regards,
Jonas

Fernando Hallberg says:

October 2, 2009 at 9:39 pm

Hi,

This script sendmail at services is UP, and not if one of services is DOWN! :D

I remove the send mail lines and create a external check for a NO ocurrence, and if exists send mail for the administrators and restart services :D

Regards,

Fernando
1. hadi says:
  
  February 10, 2010 at 5:22 am
  
  hi.. can you send to me the external script to my email hadi.utomo@gmail.com
FarhanFaisal says:

October 1, 2009 at 3:32 am

I got the same problem and I’m on FreeBSD. I modified the netstat command part, changed to this.

RPORTS=$($NETSTAT -ant -A inet | grep ‘LISTEN’ | awk ‘{ print $5}’ | cut -d’.’ -f2 | sed ‘/^$/d’ | sort -u)

But I still got problem, because of different way those services were initiated. My DNS configured to listen on specific address. So, DNS entry in netstat will be
XXX.XXX.XXX.XXX.53
but some other service like smtp will have
*.25

I still prefer a script that can monitor the port itself, checking whether its open or not.
Smile4u says:

July 14, 2009 at 7:07 am

There is an error in the “init_script”-section:
[ ! -x $NETSTAT ] && die “$MAIL command not found.”
should be like this
[ ! -x $NETSTAT ] && die “$NETSTAT command not found.”
1. Vivek Gite says:
  
  July 14, 2009 at 7:37 am
  
  Thanks for the heads-up!

Any updates?

I’ve tweaked it further. Can you test it again?

./svrmon.sh
Outputs:

-------------------------------------------------------------
Running services status @ www031.xxxtopxxxxx.net [ Tue Jul 14 02:30:24 CDT 2009 ]
-------------------------------------------------------------
 SSH			 : YES
 DNS			 : YES
 WEB			 : YES
 MAIL			 : YES
-------------------------------------------------------------
This is an automatically generated Linux service status notification by /tmp/svrmon.sh script.

Stop named:
# service named stop
Run it again:

-------------------------------------------------------------
Running services status @ www031.xxxtopxxxxx.net [ Tue Jul 14 02:30:24 CDT 2009 ]
-------------------------------------------------------------
 SSH			 : YES
 DNS			 : NO
 WEB			 : YES
 MAIL			 : YES
-------------------------------------------------------------
This is an automatically generated Linux service status notification by /tmp/svrmon.sh script.

Streametch says:

June 19, 2009 at 10:57 am

-bash-3.00# chmod +x /srv/chkserv
-bash-3.00# /srv/chkserv
————————————————————-
Running services status @ server.*****.com [ Fri Jun 19 13:53:11 EEST 2009 ]
————————————————————-
SSH :
WEB : YES
MAIL : YES
————————————————————-
This is an automatically generated Linux service status notification by /srv/chkserv script.
-bash-3.00# bash /srv/chkserv
————————————————————-
Running services status @ server.*****.com [ Fri Jun 19 13:53:23 EEST 2009 ]
————————————————————-
SSH :
WEB : YES
MAIL : YES
————————————————————-
This is an automatically generated Linux service status notification by /srv/chkserv script.
-bash-3.00# netstat -tulpn |grep ssh
tcp 0 0 :::22 :::* LISTEN 9262/sshd
-bash-3.00# grep port /srv/chkserv
ports=”22 80 25″

Any idea?
1. Streametch says:
  
  June 19, 2009 at 11:29 am
  
  So now, I replace Ports in script to:
  ports=”80 25 22″
  And Services to:
  service=”WEB MAIL SSH”
  And re-run script:
  -bash-3.00# /srv/chkserv
  ————————————————————-
  Running services status @ server.*****.com [ Fri Jun 19 14:27:53 EEST 2009 ]
  ————————————————————-
  WEB : YES
  MAIL : YES
  SSH : NO
  ————————————————————-
  This is an automatically generated Linux service status notification by /srv/chkserv script.
  
  I don’t know why :(
  1. Vivek Gite says:
    
    June 19, 2009 at 12:38 pm
    
    Ok, I will look at the script this week end and see if there is any bug that is shooting an email even if service is running.
Streametch says:

June 18, 2009 at 4:08 pm

Hey,
Thanks, now it work, but I have issue with only ssh. I run sshd service on non-standart port, and replace 22 port with my settings. After thant when I run this script I got blank value.
————————————————————-
Running services status @ server.****.com [ Thu Jun 18 19:07:24 EEST 2009 ]
————————————————————-
SSH :
WEB : YES
MAIL : YES
————————————————————-
This is an automatically generated Linux service status notification by checkstatus script.
And got fake alert :( Can you help me?
1. Vivek Gite says:
  
  June 18, 2009 at 4:30 pm
  Replace port 22 with your actual port such as #3922 in $ports i.e. from
```
ports="22 80 25"
```
  To:
```
ports="3922 80 25"
```
  1. Streametch says:
    
    June 18, 2009 at 4:38 pm
    
    Yeah, I do that at once, but still get nothing about ssh
    1. Streametch says:
      
      June 19, 2009 at 9:11 am
      
      -bash-3.00# sh /srv/chkserv
      ————————————————————-
      Running services status @ server.*****.com [ Fri Jun 19 12:08:57 EEST 2009 ]
      ————————————————————-
      SSH :
      WEB : YES
      MAIL : YES
      ————————————————————-
      This is an automatically generated Linux service status notification by /srv/chkserv script.
      -bash-3.00# grep Port /etc/ssh/sshd_config
      Port 22
      #GatewayPorts no
      -bash-3.00# ps aux|grep ssh
      root 16151 0.0 0.0 7004 2284 ? Ss 12:07 0:00 sshd: root@ttyp0
      root 23653 0.0 0.0 4624 632 ttyp0 S+ 12:09 0:00 grep ssh
      root 28047 0.0 0.0 4140 1044 ? Ss Jun18 0:00 /usr/sbin/sshd
      1. Vivek Gite says:
        
        June 19, 2009 at 9:41 am
        
        Correct way to run script is either:
        chmod +x /srv/chkserv /srv/chkserv
        OR
        bash /srv/chkserv
        To find current sshd port enter:
        netstat -tulpn
Streametch says:

June 15, 2009 at 8:47 am

Hey, this script not workin under CentOS 4.7, script messaged all service is down:
-bash-3.00# sh test_script.sh
Running services status:
SSH: No
WEB: No
MAIL: No
-bash-3.00#
But all services works fine, can you help me?
1. Vivek Gite says:
  
  June 15, 2009 at 2:19 pm
  
  Try updated script. Let me know if you need any other help.
  1. Samarasa says:
    
    June 15, 2010 at 9:57 am
    
    Where is updated scripts

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