Monit allow you to monitor process. It can restart failed process or alert when server is overloaded.
On CentOS server, you need to enable EPEL repo to install monit.
yum install epel-release -y
Install monit with
yum install monit -y
Enable monit to auto start on boot
systemctl enable monit
Start monit service
systemctl start monit
On CentOS, monit configuration file located at
vi /etc/monitrc
See monit
To monitor OpenLiteSpeed with monit on Ubuntu Server, create file
vi /etc/monit/conf-enabled/openlitespeed
Add following content
check process OpenLiteSpeed with pidfile /tmp/lshttpd/lshttpd.pid
start program = "/usr/bin/systemctl start lshttpd"
stop program = "/usr/bin/systemctl stop lshttpd"
Reload monit with
monit reload
Now monit will monitor OpenLiteSpeed, restart if required. You can check status with
monit status
If you want to monitor if web server is responding to request, you can use
check process OpenLiteSpeed with pidfile /tmp/lshttpd/lshttpd.pid
start program = "/usr/bin/systemctl start lshttpd"
stop program = "/usr/bin/systemctl stop lshttpd"
if failed host localhost port 80 protocol http then restart
gonit is a replacent for monitoring software monit. monit was removed from Debian 10 due to security issues and the devloper will not provide a patch for the security vlunerabilty in time for Debian 10 release.
You can download gonit from
https://github.com/bitnami/gonit
root@ip-172-26-14-184:~# gonit status Uptime 22h5m41s Last Check 2019-08-05 08:23:57.612314368 +0000 UTC m=+79440.116643915 Next Check 2019-08-05 08:25:57.612314368 +0000 UTC m=+79560.116643915 Pid 3162 Pid File /var/run/gonit.pid Control File /etc/gonit/gonitrc Socket File /var/run/gonit.sock Log File /var/log/gonit.log Process 'apache' status Running pid 2020 uptime 22h5m41s monitoring status monitored Process 'mysql' status Running pid 1911 uptime 22h5m41s monitoring status monitored Process 'php-fpm' status Running pid 2014 uptime 22h5m41s monitoring status monitored root@ip-172-26-14-184:~#
Monit can be used to monitor services, restart them if required. To install monit, run
apt -y install monit
To start monit, run
systemctl start monit
Monitor Apache
vi /etc/monit/conf-available/apache2-custom
Add
check process apache with pidfile /var/run/apache2/apache2.pid
group www-data
start program = "/etc/init.d/apache2 start"
stop program = "/etc/init.d/apache2 stop"
if failed host localhost port 80 protocol http then restart
if 5 restarts within 5 cycles then timeout
Activate the rule with
ln -s /etc/monit/conf-available/apache2-custom /etc/monit/conf-enabled/apache2-custom
Restart monit with
systemctl restart monit
Testing If Monit works
Open 2 terminals. On one, tail the monit logs with
tail -f /var/log/monit.log
On other terminal, stop Apache
service apache2 stop
Within 2 minutes, monit will restart apache web server.
See gonit golang replacement for monit
monit is a process monitoring service that monitor services, restart if required.
Here are monit rules used to monitor apache, php-fpm and MySQL on bitnami cloud server.
# cat apache.conf check process apache with pidfile "/opt/bitnami/apache2/logs/httpd.pid" start program = "/opt/bitnami/apache2/scripts/ctl.sh start" with timeout 90 seconds stop program = "/opt/bitnami/apache2/scripts/ctl.sh stop" with timeout 90 seconds # cat php-fpm.conf check process php-fpm with pidfile "/opt/bitnami/php/var/run/php5-fpm.pid" start program = "/opt/bitnami/php/scripts/ctl.sh start" with timeout 90 seconds stop program = "/opt/bitnami/php/scripts/ctl.sh stop" with timeout 90 seconds # cat mysql.conf check process mysql with pidfile "/opt/bitnami/mysql/data/mysqld.pid" start program = "/opt/bitnami/mysql/scripts/ctl.sh start" with timeout 90 seconds stop program = "/opt/bitnami/mysql/scripts/ctl.sh stop" with timeout 90 seconds #
monitor php-fpm
check process php7-fpm with pidfile "/var/run/php/php7.0-fpm.pid"
if cpu > 80% for 2 cycles then alert