Как установить и настроить monit для перезапуска таких сервисов, как сервер Nginx / Apache / OpenVPN при сбое на Debian или Ubuntu Linux?

$ sudo apt-get install monit

$ sudo systemctl enable monit

$ sudo systemctl status monit
$ sudo systemctl stop monit
$ sudo systemctl restart monit
$ sudo systemctl start monit

$ sudo vi /etc/monit/monitrc

$ sudo nano /etc/monit/monitrc

set alert admin@your-domain-name-here

set alert security@your-domain-name-here on { checksum, permission, uid, gid }

alert vivek@server1.cyberciti.biz with reminder on 5 cycles

set httpd port 2812 and
use address localhost # only accept connection from localhost
allow localhost # allow localhost to connect to the server and
allow admin:monit # require user 'admin' with password 'monit'

$ sudo vi /etc/monit/conf-available/foo

check process foo
matching "foo"
start program = "/etc/init.d/foo start"
stop program = "/usr/bin/killall foo"

$ sudo ln -s /etc/monit/conf-available/foo /etc/monit/conf-enabled/

$ monit -t
Control file syntax OK

$ sudo /etc/init.d/monit reload

OR

$ sudo systemctl reload monit

$ sudo vi /etc/monit/conf-available/openvpn

check process openvpn with pidfile /var/run/openvpn/server.pid
group nogroup
start program = "/etc/init.d/openvpn start"
stop program = "/etc/init.d/openvpn stop"
if failed host localhost port 1194 then restart
if 5 restarts with 5 cycles then timeout
depend on openvpn_bin

check file openvpn_bin with path /usr/sbin/openvpn
group nogroup
include /etc/monit/templates/rootbin

$ sudo ln -s /etc/monit/conf-available/openvpn /etc/monit/conf-enabled/

$ monit -t
Control file syntax OK

$ sudo /etc/init.d/monit reload

OR

$ sudo systemctl reload monit

$ cat /etc/monit/conf-available/mysql

check process mysqld with pidfile /var/run/mysqld/mysqld.pid
group database
group mysql
start program = "/etc/init.d/mysql start"
stop program = "/etc/init.d/mysql stop"
if failed host localhost port 3306 protocol mysql with timeout 15 seconds for 3 times within 4 cycles then restart
if failed unixsocket /var/run/mysqld/mysqld.sock protocol mysql for 3 times within 4 cycles then restart
if 5 restarts with 5 cycles then timeout
depend mysql_bin
depend mysql_rc

check file mysql_bin with path /usr/sbin/mysqld
group mysql
include /etc/monit/templates/rootbin

check file mysql_rc with path /etc/init.d/mysql
group mysql
include /etc/monit/templates/rootbin

$ cat /etc/monit/conf-available/nginx

check process nginx with pidfile /var/run/nginx.pid
group www
group nginx
start program = "/etc/init.d/nginx start"
stop program = "/etc/init.d/nginx stop"
if 5 restarts with 5 cycles then timeout
depend nginx_bin
depend nginx_rc

check file nginx_bin with path /usr/sbin/nginx
group nginx
include /etc/monit/templates/rootbin

check file nginx_rc with path /etc/init.d/nginx
group nginx
include /etc/monit/templates/rootbin

$ cat /etc/monit/conf-available/apache2

check process apache with pidfile /var/run/apache2/apache2.pid
group www
group apache
start program = "/etc/init.d/apache2 start"
stop program = "/etc/init.d/apache2 stop"
if 4 restarts within 20 cycles then timeout
if failed host localhost port 80 with protocol http and request "/server-status" with timeout 25 seconds for 4 times within 5 cycles then restart
depend apache_bin
depend apache_rc

check file apache_bin with path /usr/sbin/apache2
group apache
include /etc/monit/templates/rootbin

check file apache_rc with path /etc/init.d/apache2
group apache
include /etc/monit/templates/rootbin

$ cat /etc/monit/conf-available/openssh-server

check process sshd with pidfile /var/run/sshd.pid
group system
group sshd
start program = "/etc/init.d/ssh start"
stop program = "/etc/init.d/ssh stop"
if failed host localhost port 22 with proto ssh then restart
if 5 restarts with 5 cycles then timeout
depend on sshd_bin
depend on sftp_bin
depend on sshd_rc
depend on sshd_rsa_key
depend on sshd_dsa_key

check file sshd_bin with path /usr/sbin/sshd
group sshd
include /etc/monit/templates/rootbin

check file sftp_bin with path /usr/lib/openssh/sftp-server
group sshd
include /etc/monit/templates/rootbin

check file sshd_rsa_key with path /etc/ssh/ssh_host_rsa_key
group sshd
include /etc/monit/templates/rootstrict

check file sshd_dsa_key with path /etc/ssh/ssh_host_dsa_key
group sshd
include /etc/monit/templates/rootstrict

check file sshd_rc with path /etc/ssh/sshd_config
group sshd
include /etc/monit/templates/rootrc

$ cd /etc/monit/conf-enabled/
$ sudo ln -s /etc/monit/conf-available/openssh-server
$ sudo ln -s /etc/monit/conf-available/nginx
$ sudo ln -s /etc/monit/conf-available/mysql
$ sudo ln -s /etc/monit/conf-available/apache2
$ sudo monit -t
$ sudo /etc/init.d/monit reload

$ sudo monit summary

The Monit daemon 5.16 uptime: 1h 9m

Process 'openvpn' Running
File 'openvpn_bin' Accessible
System 'blr-nixcraft-do-0001' Running

$ sudo monit status

$ sudo monit status openvpn

The Monit daemon 5.16 uptime: 1h 15m

Process 'openvpn'
status Running
monitoring status Monitored
pid 31577
parent pid 1
uid 65534
effective uid 65534
gid 65534
uptime 1h 17m
threads 1
children 0
memory 6.1 MB
memory total 6.1 MB
memory percent 1.3%
memory percent total 1.3%
cpu percent 0.0%
cpu percent total 0.0%
port response time 2.091 ms to [localhost]:443 type TCP/IP protocol DEFAULT
data collected Sun, 25 Jun 2017 00:12:40

$ sudo tail -f /var/log/monit.log

[IST Jun 24 23:54:40] info : Starting Monit HTTP server at [localhost]:2812
[IST Jun 24 23:54:40] info : Monit HTTP server started
[IST Jun 24 23:54:40] info : 'blr-nixcraft-do-0001' Monit reloaded

$ grep foo /var/log/monit.log
$ grep sshd /var/log/monit.log
$ grep openvpn /var/log/monit.log

[IST Jun 24 22:55:28] info     : 'openvpn' start: /etc/init.d/openvpn

http://server1.sedicomm.com:2812