Hmm… so it is not possible to set an Alias/rename “Interface 02” inside of checkmk so that it reads i.e. “WAN (Interface 02)” in all screens?
I am surprised that this is not possible - I thought that this is a kinda basic feature to make the collected datapoints clear. O.o
Sadly I can’t change anything about the “Interface 02” name on the server as the Untangle NG Firewall does not provide that functionality - in Untangle the interface “eth0” is actually called “External” (!?) - why this turns into “Interface 02” through SNMP I do not know. 
I’d really like to be able to do that kind of customization inside of checkmk, I am sad that this is not possible.
Thank’s again for your reply!