Monit¶

sudo apt install monit

sudo nano /etc/monit/monitrc

set daemon 60
set logfile syslog facility log_daemon
set idfile /var/lib/monit/id
set statefile /var/lib/monit/state

# Mail-Konfiguration
set mailserver localhost port 25
set mail-format {
  from: monit@example.com
  subject: monit alert -- $EVENT $SERVICE
  message:
    Monit $ACTION $SERVICE at $DATE on $HOST: $DESCRIPTION.
}
set alert admin@example.com

# Web-Interface
set httpd port 2812 and
    allow admin:password

sudo nano /etc/monit/conf.d/system

check system $HOST
  if loadavg (1min) > 10 then alert
  if loadavg (5min) > 6 then alert
  if memory usage > 75% then alert
  if cpu usage (user) > 70% for 5 cycles then alert

check filesystem rootfs with path /
  if space usage > 80% then alert
  if inode usage > 85% then alert

check filesystem var with path /var
  if space usage > 85% then alert

check process nginx with pidfile /var/run/nginx.pid
  start program = "/etc/init.d/nginx start"
  stop program = "/etc/init.d/nginx stop"
  if failed host localhost port 80 protocol http then restart
  if 5 restarts within 5 cycles then timeout

check process apache2 with pidfile /var/run/apache2/apache2.pid
  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

check process postfix with pidfile /var/spool/postfix/pid/master.pid
  start program = "/etc/init.d/postfix start"
  stop program = "/etc/init.d/postfix stop"
  if failed port 25 protocol smtp then restart
  if 5 restarts within 5 cycles then timeout

check process dovecot with pidfile /var/run/dovecot/master.pid
  start program = "/etc/init.d/dovecot start"
  stop program = "/etc/init.d/dovecot stop"
  if failed port 143 protocol imap then restart
  if 5 restarts within 5 cycles then timeout

check process mysql with pidfile /var/run/mysqld/mysqld.pid
  start program = "/etc/init.d/mysql start"
  stop program = "/etc/init.d/mysql stop"
  if failed port 3306 protocol mysql then restart
  if 5 restarts within 5 cycles then timeout

check network public with interface eth0
  if failed link then alert
  if changed link then alert
  if saturation > 90% then alert
  if download > 10 MB/s then alert
  if upload > 10 MB/s then alert

sudo monit -t

sudo systemctl restart monit
sudo systemctl enable monit

sudo monit status
sudo monit summary