Bridge Group replacement

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Jun 3rd, 2009
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I am moving from a 7500 router to a 6500 platform.

I use bridge groups with the 7500 series, as I see bridge groups are not availible in the 6500 platform.

What can I use as a replacement?

Here is one of my applications:

Ethernet interface bridged to a ATM sub interface.



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Overall Rating: 5 (1 ratings)
Daniel Graham Wed, 06/03/2009 - 11:15
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Just want to clarify,

What command can I use on the 6500 platform that will act simular to a bridge-group?


glen.grant Wed, 06/03/2009 - 13:50
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Pretty sure bridging is available if you are running a correct feature set . We use bridging on a Sup 720 , think we have enterprise services feature set .

Daniel Graham Wed, 06/03/2009 - 19:00
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Its in the feature set I have, but I am unable to find a way to add an atm sub interface to a bridge-group.

Giuseppe Larosa Wed, 06/03/2009 - 23:19
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Hello Dan,

while I was looking for another thread I've found the following config example:

Router(config)# interface serial3/0/0

Router(config-if)# no ip address

Router(config_if)# encapsulation ppp

Router(config-if)# bridge-domain 100 dot1q

Router(config-if)# service-policy output vlan-inner-100

Router(config-if)# shutdown

Router(config-if)# no shutdown

Router(config-if)# end


Enables RFC 1483 ATM bridging or RFC 1490 Frame Relay bridging to map a bridged virtual LAN (VLAN) to an ATM permanent virtual circuit (PVC) or Frame Relay data-link connection identifier (DLCI).

I would give it a try

Hope to help


Daniel Graham Fri, 06/05/2009 - 07:21
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Does anyone know what the difference between these is?

bridge-domain 40 dot1q


bridge-domain 40 access


Daniel Graham Fri, 06/05/2009 - 07:35
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Well, I figured that out.

I will test and hopefully it works out.


Daniel Graham Fri, 06/05/2009 - 08:19
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Problem already:

%bridge-domain rejected: unable to allocate port

Is there a limit to how many interfaces can belong to a bridge-domain?

Giuseppe Larosa Fri, 06/05/2009 - 08:41
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Hello Dan,

as I wrote I haven't tried this already.

I think it is time to look at the details of your C7600 chassis.

Have you got an ATM PA on a Flewwan or it an ATM SPA on a SIP linecard

RFCs 1483 and 2684 ATM Bridging is reported on enhanced Flexwan datasheet

SIP400 datasheet doesn't report the same feature

So I'm afraid it can be unsupported depending on your hardware.

Hope to help


Daniel Graham Fri, 06/05/2009 - 08:47
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I have a 6500 with ATM PA on FlexWAN.

I was able to use bridge-domains on several interfaces, after adding several I started getting %bridge-domain rejected: unable to allocate port

Maybe I need to look at a different option altogether. Not sure what though.


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