Bash - start multiple services if any is running CentOS 6.8 - bash

I want to check if one, (or all) services are running, if yes, stop it
#!/bin/bash
# Define an array of processes to be checked.
# If properly quoted, these may contain spaces
check_process=( "nagios" "httpd" )
for p in "${check_process[#]}"; do
if pgrep "$p" > /dev/null; then
echo "Process \`$p' is running, stopping it"
service $p stop
else
echo "Process \`$p' is not running"
fi
done
For httpd service all works fine, script detects correctly httpd service state.
I have issues detecting nagios service state.
But although nagios service is not running, script shows it's running
Process `nagios' is running, stopping it
Stopping nagios:No lock file found in /usr/local/nagios/var/nagios.lock
Process `httpd' is not running
Is there any more elegant way of detecting if nagios service is running without checking if nagios.lock file exists ?
pgrep nagios shows no output when service is not tunning.

I gave up, this works fine for me:
although ps -ef | grep -v grep | grep $service | wc -l shows 0 for nagios, script reports that nagios service is running
#!/bin/bash
logfile=/tmp/stop_nagios.txt
exec >> $logfile
exec 2>&1
service=httpd
if (( $(ps -ef | grep -v grep | grep $service | wc -l) > 0 ))
then
echo "$service is running, stopping it"
date
sudo service $service stop
else
echo "$service is not running"
fi
# check nagios service
FILE=/usr/local/nagios/var/nagios.lock
if test -f "$FILE"; then
echo "nagios service is running, stopping it"
date
sudo service nagios stop
else
echo "nagios is not running..."
fi

Related

how to determine if the service exists in shell [duplicate]

What is the best way in bash to check if a service is installed? It should work across both Red Hat (CentOS) and Ubuntu?
Thinking:
service="mysqld"
if [ -f "/etc/init.d/$service" ]; then
# mysqld service exists
fi
Could also use the service command and check the return code.
service mysqld status
if [ $? = 0 ]; then
# mysqld service exists
fi
What is the best solution?
To get the status of one service without "pinging" all other services, you can use the command:
systemctl list-units --full -all | grep -Fq "$SERVICENAME.service"
By the way, this is what is used in bash (auto-)completion (see in file /usr/share/bash-completion/bash_completion, look for _services):
COMPREPLY+=( $( systemctl list-units --full --all 2>/dev/null | \
awk '$1 ~ /\.service$/ { sub("\\.service$", "", $1); print $1 }' ) )
Or a more elaborate solution:
service_exists() {
local n=$1
if [[ $(systemctl list-units --all -t service --full --no-legend "$n.service" | sed 's/^\s*//g' | cut -f1 -d' ') == $n.service ]]; then
return 0
else
return 1
fi
}
if service_exists systemd-networkd; then
...
fi
Hope to help.
Rustam Mamat gets the credit for this:
If you list all your services, you can grep the results to see what's in there. E.g.:
# Restart apache2 service, if it exists.
if service --status-all | grep -Fq 'apache2'; then
sudo service apache2 restart
fi
On a SystemD system :
serviceName="Name of your service"
if systemctl --all --type service | grep -q "$serviceName";then
echo "$serviceName exists."
else
echo "$serviceName does NOT exist."
fi
On a Upstart system :
serviceName="Name of your service"
if initctl list | grep -q "$serviceName";then
echo "$serviceName exists."
else
echo "$serviceName does NOT exist."
fi
On a SysV (System V) system :
serviceName="Name of your service"
if service --status-all | grep -q "$serviceName";then
echo "$serviceName exists."
else
echo "$serviceName does NOT exist."
fi
In systemd (especially in Debian), it doesn't seems to work properly using the various answers from here. For some services like pure-ftpd if it's in disabled mode, it will not show up in service list when you trigger this command:
systemctl --all --type service
and when you start again the pure-ftpd with systemctl start pure-ftpd the list will appear again. So listing the service using systemctl --all --type service will not work for all services. Take a look at this for more information.
So, this is the best code so far (improvement from #jehon's answer) to check if a service is exist (even it has status inactive, dead or whatever status it is):
#!/bin/bash
is_service_exists() {
local x=$1
if systemctl status "${x}" 2> /dev/null | grep -Fq "Active:"; then
return 0
else
return 1
fi
}
if is_service_exists 'pure-ftpd'; then
echo "Service found!"
else
echo "Service not found!"
fi
Explanation:
If systemctl status found a service, it must have a text 'Active:' we filter using grep and it would return 0. If there is no 'Active:' text it would return 1.
If systemctl status does not find the 'Active:' text, it will print out a standard error. So, I put redirection 2> /dev/null to redirect the standard error. For example, if you are looking for the non existence service, you would get this error message if you don't put that error redirection:
Unit pure-ftpdd.service could not be found.
We don't want to have the above standard error message if you are doing scripting
EDIT:
Another method is to list out unit files which able to detect disabled service as pointed by #Anthony Rutledge for Debian system:
systemctl list-unit-files --type service | grep -F "pure-ftpd"
But using this method will not always work especially for older system because some unit files might not be detected using this command as explained in here. Also, using this method is slower if you have large unit-files that need to be filtered (as commented by #ygoe about heavy load on a small computer).
To build off of Joel B's answer, here it is as a function (with a bit of flexibility added in. Note the complete lack of parameter checking; this will break if you don't pass in 2 parameters):
#!/bin/sh
serviceCommand() {
if sudo service --status-all | grep -Fq ${1}; then
sudo service ${1} ${2}
fi
}
serviceCommand apache2 status
After reading some systemd man pages ...
https://www.freedesktop.org/software/systemd/man/systemd.unit.html
... and systemd.services(5)....
... and a nice little article ...
https://www.linux.com/learn/understanding-and-using-systemd
I believe this could be an answer.
systemctl list-unit-files --type service
Pipe to awk {'print $1'} to just get a listing of the service units.
Pipe to awk again to get the service names exclusively. Change the field separator to the period with -F.
awk -F. {'print $1'}
In summary:
systemctl list-unit-files --type service | awk {'print $1'} | awk -F. {'print $1'}
With variation and augmentation of the base solution, you can determine the state of your system's services by combining a for loop with systemctl is-active $service.
#!/bin/sh
service=mysql
status=$(/etc/init.d/mysql status)
print "$status"
#echo $status > /var/log/mysql_status_log
var=$(service --status-all | grep -w "$Service")
if [ "output" != "" ]; then
#executes if service exists
else
#executes if service does not exist
fi
$Service is the name of the service you want to know if exists.
var will contain something like
[+] apache2
if the service does exist
if systemctl cat xxx >/dev/null 2>&1; then
echo yes
fi
Try this, as ps command can be used in both Ubuntu&RHEL, this should be work in both platform.
#!/bin/bash
ps cax | grep mysqld > /dev/null
if [ $? -eq 0 ]; then
echo "mysqld service exists"
else
echo "mysqld service not exists"
fi

Check if a process is running and if not, restart it using Cron

I have created restart.sh with followin code
#!/bin/bash
ps -aux | grep sidekiq > /dev/null
if [ $? -eq 0 ]; then
echo "Process is running."
else
echo "Process is not running."
fi
To check if sidekiq process is running or not. I will put this script in cron to run daily so if sidekiq is not running, it will start automatically.
My problem is, with
ps -aux | grep sidekiq
even when the process is not running, it shows
myname 27906 0.0 0.0 10432 668 pts/0 S+ 22:48 0:00 grep --color=auto sidekiq
instead of nothing. This gets counted in grep hence even when the process is not running, it shows as "sidekiq" process is running. How to not count this result ? I believe I have to use awk but I am not sure how to use it here for better filtering.
To exclude the grep result from the ps output. Do
ps -aux | grep -v grep | grep sidekiq
(or) do a regEx search of the process name, i.e. s followed by rest of the process name.
ps -aux | grep [s]idekiq
To avoid such conflicts in the search use process grep pgrep directly with the process name
pgrep sidekiq
An efficient way to use pgrep would be something like below.
if pgrep sidekiq >/dev/null
then
echo "Process is running."
else
echo "Process is not running."
fi

bash script: to check if Apache server is up and running

I am new to bash scripting and trying to figure out why the below script is outputting that Apache server is not running whereas it is running properly.
ps cax | grep httpd
if [ $? -eq 0 ]; then
echo "Process is running."
else
echo "Process is not running."
fi
I'm running it on Ubuntu 14.04.2 LTS
Also, how do I make changes to the script that this can test apache server installed on another machine.
Kindly help
This is a working sample of bash script which check the apache status, restart it automatically if down, and alert by telegram bot within unicode emoji.
#!/bin/bash
telegram=(xxxxx, yyyyyy)
if ! pidof apache2 > /dev/null
then
# web server down, restart the server
echo "Server down"
/etc/init.d/apache2 restart > /dev/null
sleep 10
#checking if apache restarted or not
if pidof apache2 > /dev/null
then
for i in "${telegram[#]}"
do
curl -s -X POST https://api.telegram.org/botxxxxxx:yyyyyyyyyyyyyyyyyyyyyyyyyy/sendMessage -d chat_id="$i" -d text="`echo -e '\U0001F525'` Apache stoped on Molib Stage. Automatically restarted succesfully."
done
else
for i in "${telegram[#]}"
do
curl -s -X POST https://api.telegram.org/botxxxxxx:yyyyyyyyyyyyyyyyyyyyyyyyyy/sendMessage -d chat_id="$i" -d text="`echo -e '\U0001F525'` Apache stoped on Molib Stage. Automatically restart failed. Please check manually."
done
fi
fi
Use this:
service apache2 status
Or this:
service --status-all | grep apache2
Instead of httpd try to grep "apache2". To be sure try to check services with the next command and decide the registered name of the apache webserver:
service --status-all
Try and see - simply simplest, most didactic here and well working on Ubuntu 20.04:
catching output of status to bash variable
"if" status includes substring (from "Active:" statement) - do job you wanted
"else" - do another job you defined
#!/bin/bash
servstat=$(service apache2 status)
if [[ $servstat == *"active (running)"* ]]; then
echo "process is running"
else echo "process is not running"
fi
This work perfect in an old Debian. Remember to run with bash and not with sh.
In Centos replace with httpd.
#!/bin/bash
if [ $(/etc/init.d/apache2 status | grep -v grep | grep 'apache2 is running' | wc -l) > 0 ]
then
echo "Process is running."
else
echo "Process is not running."
fi
## Plz run this script .. its working
------------------------------------------------
ps cax | grep httpd
if [ $? -eq 1 ]
then
echo "Process is running."
else if [ $? -eq 0 ]
echo "Process is not running."
fi
fi
----------------------------------------------
This is menu driven one stop shell script in which you can check the firewall,apache or any other webservices ,you can start or stop the services just by choosing the option in below script
echo "welcome please select your options"
read choice
firewall=`sudo systemctl status firewalld`
apache=`sudo systemctl status apache2`
firewall1=`sudo systemctl stop firewalld`
apache1=`sudo systemctl stop apache2`
startrfirewall=`sudo systemctl start firewalld`
startapache=`sudo systemctl start apache2`
case $choice in
1) status of the firewall is $firewall
;;
2) status of apache is $apache
;;
3) echo stop firewall by $firewall1
;;
4) echo stop apache by $apache1
;;
5) echo start firewall by $startrfirewall
;;
6) echo start apache by $startapache
;;
*) echo exit
esac
I put this together based on the above and made so can use other services.
Hope this helps.
#!/bin/bash
# Must be running as root or via sudo permissions to be able to restart
# Put your process name restart command line in
PROCESS_NAME=httpd
if ! pidof $PROCESS_NAME > /dev/null
then
# web server down, restart the server
echo "Server $PROCESS_NAME down"
/usr/sbin/apachectl restart > /dev/null
echo "Tried restart of $PROCESS_NAME. Waiting 10 seconds to settle."
# wait ten
sleep 10
#checking if process restarted or not
if pidof $PROCESS_NAME > /dev/null
then
echo "$PROCESS_NAME was down but is now up."
else
echo "$PROCESS_NAME is still down. Please take some action."
fi
else
echo "Server $PROCESS_NAME up."
fi

To check whether nohup service is running or not using shell script?

I had created a nohup service using the below command in putty.
nohup php /var/www/html/XYZ/sample.php &
This command executes the sample.php file in background.
Now what i need is i want a shell script which checks whether this service is running or not.Incase if the service is not running i want that shell script to create a service by its own. Below is the code what i tried.
#!/bin/bash
email_to="xyz#gmail.com";
export DISPLAY=:0.0
PIDS=`ps -aux | grep sample.php|awk '{print $2}'`
if [ -z "$PIDS" ]; then
echo "$(date) - The service is not running. Sending email to :$email_to" >> /var/www/html/XYZ/sample.php;
echo "SERVICE is not running - $(date)" | mail -s "service is not running - $(date)" $email_to
echo "" >> /var/www/html/XYZ/sample.php;
exit 1
else
echo "$(date) - Service already running. Sending email to : $email_to" >> /var/www/html/XYZ/sample.php;
echo "SERVICE is running - $(date)" | mail -s "SERVICE is running - $(date)" $email_to
fi
when i execute the file i get the mail as service is running ,and once i kill the sample.php and when i get execute this file i get the same mail "as service is running" but its wrong ,so can anyone direct me where have i gone wrong?
where have i gone wrong?
With ps -aux | grep sample.php, the grep is finding sample.php in its own process command line grep sample.php, also output by ps. This can be avoided by modifying the grep command so that it doesn't contain sample.php literally, e. g. grep 'sample\.php' (which by the way averts the risk of matching another character instead of the .). You'll probably also need wide output from ps to not truncate the command, so change the above pipeline to ps waux | grep 'sample\.php'.

Tomcat 7 monitoring with e-mail notifications

I've been looking for a bit but can't find a free/open-source tomcat 7 monitoring tool that will send out e-mails or notifications when certain situations occur. For example when CPU utilization spikes or RAM is consistently full. Things Like that.
I've looked at JMelody and Psi-Probe and neither of them have the ability to send e-mails when some event occurs.
You can take a look at jboss RHQ
https://docs.jboss.org/author/display/RHQ/Alerts
This might help someone!!
If one do not want to use any monitoring tool, then set up an email configurtion in Ubuntu server using mailutils package.
https://rianjs.net/2013/08/send-email-from-linux-server-using-gmail-and-ubuntu-two-factor-authentication
https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-postfix-as-a-send-only-smtp-server-on-ubuntu-14-04
To monitor Tomcat status you can use below script and set up cron job which runs every minute/hour/day according to your needs.
#!/bin/bash
TOMCAT_HOME=/opt/tomcat
PUBLIC_IP=`wget http://ipecho.net/plain -O - -q ; echo`
EMAIL_BODY="Hi Admin,\n\n$PUBLIC_IP Tomcat is down at $(date -d "+330 minutes" +"%Y-%m-%d %T") IST, Please take necessary action.\n\n\nDo not reply to this email as it is auto generated by Ubuntu system\n"
tomcat_pid() {
echo `ps aux | grep org.apache.catalina.startup.Bootstrap | grep -v grep | awk '{ print $2 }'`
}
start() {
pid=$(tomcat_pid)
if [ -n "$pid" ]
then
echo "Tomcat is already running (pid: $pid)"
else
# Start tomcat
echo "Starting tomcat"
/bin/sh $TOMCAT_HOME/bin/startup.sh
fi
return 0
}
pid=$(tomcat_pid)
if [ -n "$pid" ]
then
echo "Tomcat is running with pid: $pid"
#stop
else
echo "Tomcat is not running"
# send an email alert then start
echo -e $EMAIL_BODY | mail -s "$PUBLIC_IP Tomcat is down" user#email.com
echo "Mail sent"
#remove cache and release memory occupied by heavy processes
start
fi
exit 0

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