I use a VPN connection on my ubuntu machine and want to monitor it properly. I installed the check_mk agent on the machine and it runs smoothly.
The VPN interface is dynamically created once the the VPN connection is established --> interface name: tun0
If the interface is up, I get the proper status: OK - [tun0] (up) speed unknown …
My problem is if the VPN connection goes down. In this case, the VPN interface is not present anymore and check_mk only reports this as WARNING. I would like to have the status CRITICAL once the interface is not present anymore.
What I get currently if the interface is down:
Status detail: UNKN - No such interface
What I tried, is to create a manual rule for the host by adding a new rule in “Network interfaces and switchports”. Here I used “Map operational states”. I thought that assigning “6 - not present” to “CRIT” would do the job but it doesn’t.
It seems I need to use a different check but I don’t know which one. Maybe some of you can help.
thx in advance.
p.s. I looked at the “VPN tunnel” check, but as the IP of the VPN gateway is not fixed, this doesn’t help either.