[Observium] recreate interface to down/up -event

Hallo, i have the following problem. I server of mine a VPN-Service. This vpn-service restart some times (and with it it recreate a network interface with the same name "vpn-interface"). Observium delete the interface and create a new one (with the same name).

The Question, is it possible to detect it and make a down up event out of it (and a mac change)? So it will use the same rrds, graphs and so on.

Nice Wishes Geno