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New Member

8510, IRB, VLANs and BVIs

If I create a VLAN on a subinterface and assign it to a bridge group:


interface FastEthernet1/0/7.1

description Line 5 PLC subnet

encapsulation isl 2

ip address

no ip redirects

bridge-group 1

bridge-group 1 spanning-disabled


and then assign the bridge group to a BVI, can I use IP unnumbered on the BVI or do I need an addy?

Also, do I need an IP addy for IRB to work and to get VLAN to VLAN traffic?

Alternatively, can I do IP unnumbered for the VLAN subinterface?

New Member

Re: 8510, IRB, VLANs and BVIs

You can use Ip unnumbered on the BVI but I would not use the sub-interface for this, it would be better to put the ip address on a loopback and unnumber the BVI to that. You do need an IP address for IRB to work.

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