We can integrate script checks into Consul.  To do so with Nagios:

  • Install nagios-plugins-basic. That will contain some basic checks such as disk util, and cpu load

apt-get install nagios-plugins-basic

  • There are also other custom Nagios checks on the internet for eg: checks for Open Connections

Put this script in:

/usr/lib/nagios/plugins

  • Create JSON config (connections.json) and put it under /etc/consul.d/client

{
“check”: {
“name”: “Open Connections”,
“interval”: “60s”,
“args”: [“/usr/lib/nagios/plugins/check_connections”, “-c”, “{{connection_limit_critical}}”, “-w”, “{{connection_limit_warn}}” ],
“status”: “passing”
}

}

  • Restart Consul service
  • You should see this on Consul UI