foxbatreco Thu, 06/12/2008 - 23:36
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For using bridge mode u have to enable integrated routing and bridge mode with 'bridge irb command'.Then u create a brigde virtual interface(BVI) which behaves like representing entire bridge group pointing to routed interfaces in the router.

BVI needs to be assigned a BVI group no.This no.acts as the relation pointer between the BVI interface & the bridge group.

like below:

int fa0/1

no ip address

duplex auto

bridge-group 64

int bvi64

ip address

ip access-group 130 in

ip nat outside

ip nat inside source list 5 inteface BVI64 overload

ip route

bridge 64 protocol ieee

bridge 64 route ip

the sample above shows BVI being enabled with grpno. 64.this is further referenced to the actual physical interfaces as they arent involved in actual routing.

the bridge group is referenced with the protocol it will this case IP.

Pls rate/mark if this helps!!!

ntmanjunath Mon, 06/16/2008 - 08:41
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We are using Leased line link with ISP between two Cisco router A and B.The A router connected to Head Office and similarly B router connected to Branch Office.The concept is we have to configure the bridge between the two routers.This will be point to point connection.

What would be the configuration for both the routers?


paolo bevilacqua Mon, 06/16/2008 - 09:42
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do not use bridge for this application. Use nornal IP addressing with different subnet for each sites.

Using bridging expose you to broadcast traffic crossing the link, difficulty in diagnosis, impossiblity of doing poer QoS, end other problems. Generally speaking, bridging is a poor practice and should be avoided whenever possible.


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