Check_MK: Adjust alert thresholds/levels for single check on host in WATO

We are monitoring the C drive of a Host and are running this system pretty lean:

I want to change it so it Warns at 90% and Criticals at 95%.  This can be done for manually inventoried checks, but I used WATO with auto-inventory for the entire environment, so I want to keep modifications to checks in WATO also.  This is done by using Rules.

Since we only want to modify a single check for a specific host, visit the Services page of the Host and click on the specific service, in this case "Filesystem C:/"

Should take you to here:

Next we are going to click on the "View and Edit Parameters for this Service" icon next to Service Icons:

This page will show you the thresholds (levels) we are using:

To edit these thresholds, click on Filesystems (used space and growth).  This will take us to a page that will allow us to create a custom rule:

Click on "Create Mount point for specifc rule for".  This page has many parameters you can modify for this check, including levels:

In the Parameters section put a check next to "Levels for filesystem" and input the levels you want to use:

On the bottom of this page click Save.

A summary of the Rule will show up on the page:

Make sure to commit the changes to Check_MK:

 

We can make sure the threshold change worked by going back into the Hosts' Service check:

Rules can be used in many ways, for example a single rule can modify all checks of a specific type on every host.

Monitor CentOS 7 Client with OMD / Check_MK

Quick instructions for adding a CentOS 7 client to OMD / Check_MK.

Log into the CentOS 7 client via ssh/terminal. Install check-mk-agent

# yum install check-mk-agent



Once installed, edit xinetd config:

# nano /etc/xinetd.d/check-mk-agent

Uncomment only_from and add IP of your OMD/Check_MK server



Save and Close

Start and enable startup for xinetd service:

# systemctl start xinetd.service
# systemctl enable xinetd.service

Add port 6556 to firewall:

# firewall-cmd --add-port=6556/tcp --permanent
# firewall-cmd --reload
# firewall-cmd --list-all

Now you can add the client to your Check_MK panel via New Host and it will automatically add the checks.

Update OMD (Open Monitoring Distribution) from 1.20 to 1.30

Open Monitoring Distribution was recently updated to 1.30, here is how to update.  My instance of OMD was installed with the consol.de repo.  I recommend this because it is an easy way to install and update OMD, I am using the stable release, and CentOS 7 as the linux distro.  Bad part is check_mk updates faster than OMD! ;)

Next we can check for update:

Next we will install the 1.30 bits:

With the bits installed we need to log into the monitoring site so it can be updated:

Check current version:

Run omd update

Update!

Start site

With the bits updated and site started the GUI should now be working.  Now its time to update all of my clients from check_mk 1.2.4p5 to 1.2.6p12, the new agents are found in /share/check_mk/agents directory of your site folder.