Hello Gie
Just an update on this one. Although Cisco documentation seems to indicate that it is possible to use the same VRRP ID on different subinterfaces of the same physical interface, actually going into the lab and trying it out shows different results:
R1(config)#int gi 0/0.1
R1(config-subif)#encapsulation dot1Q 10
R1(config-subif)#ip address 192.168.1.1 255.255.255.0
R1(config-subif)#vrrp 10 ip 192.168.1.254
R1(config-subif)#exit
R1(config)#int gi 0/0.2
R1(config-subif)#encapsulation dot1Q 20
R1(config-subif)#ip address 192.168.2.1 255.255.255.0
R1(config-subif)#vrrp 10 ip 192.168.2.254
% Cannot create new VRRP group
It doesn’t give a further explanation as to why the creation of the VRRP group fails. However, it does seem to be because the same VRRP ID is being used on multiple subinterfaces of the same physical interface. I tried using the same VRRP ID on different physical interfaces and I was successful.
I’m using IOSv Version 15.9(3)M6 on Cisco’s CML platform. It may be that in previous versions of IOS this was possible and this is why we see it in the documentation, but it has changed in the more recent versions.
Laz