CheckMK Distributed Monitoring


The purpose of this guide is to show the strength and flexibility of CheckMK’s distributed monitoring. As you add hosts and services, the requirements can grow. It can be easy to get in the rut of adding more CPU and RAM until you have a monstrosity of a server that you cannot expand anymore.

Centrally monitoring all sites may not even work. The central CheckMK server may not have access to all of the remote devices.

Pre-requisites and Installation

To start off, we will need another CheckMK instance. If you do not already have one, check out the Introduction to CheckMK guide. Once you have CheckMK installed and a new unique site setup, the rest is trivial

Distributed monitoring also involves the slave listening on TCP/6557 so we need to open that up

[root@chckmk2 ~]# firewall-cmd --zone=public --add-port=6557/tcp --permanent
[root@chckmk2 ~]# firewall-cmd --reload

[root@chckmk2 ~]# su - second

OMD[second]:~$ omd config

We then enable distributed monitoring and enable livestatus

omd config - Distributed Monitoring
Select “Distributed Monitoring”
omd livestatus
omd livestatus

Enable livestatus which will listen on port 6557

Configure Connection

From the main site, in our series navigate to Distributed Monitoring

Distributed Monitoring
Distributed Monitoring
New Connection
New Connection
Second connection options
Fill out the appropriate options.
Login to second site
Select the credentials that have access to login to the second site.
Login again!
Save changes
Save changes

Use Connection

Now that we have the connection, how do we actually use it? One of the easiest and likely ways is to have a folder configured just with that monitoring site

New Folder
Create a folder with a monitored site

Next I added a host and put it in this new folder. Here you can see CheckMK is smart enough to know only the “second” site needs to be reloaded due to the changes that only affect it.

Activate second site changes
Activate second site changes

Final Words

This article was mostly pictures but hopefully the point comes across. That point is how flexible and easy it is to setup distributed monitoring via CheckMK.

Author: David Chapman

I started my IT career in the very late 1990's as a systems administrator for a benefits company. I have always enjoyed learning new technologies and helping people fix problems which has lead me through a few different positions over the past 20+ years.