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New Member

DLSW - NO IP Address - FastEthernet.

Dear All Expert,

Good Morning.

I would like to seek for your advice on my below concern.

If I migrate below config


interface FastEthernet0/0

ip address

bridge-group 1


To Sub-interface fa0/0.1 but without any IP configured.


interface fastethernet 0/0

no ip address


interface fastethernet 0/0.1

encapsulation dot1q 1 native

no ip address

bridge-group 1



So, Above configuration is it able to work fine ? FYI - I try to add IP to fa0/0.1 before and it is working ok. Now wondering is it able to work if without IP address configured.

Please guide and highlight me.

Maybe sharing a good documentation related to above subject is highly appreciated. (^_^)



Hall of Fame Super Silver

Re: DLSW - NO IP Address - FastEthernet.


We might need some additional information about your particular situation to be able to give a really good answer. But in general the purpose of configuring bridge-group 1 is to allow the router to process non-IP traffic, such as IBM SNA, and to allow DLSW to forward that traffic (encapsulated in IP). So there is no need for the IP address on the interface as far as DLSW is concerned. The IP address on the interface allows non-SNA IP traffic to be routed on that interface.

So in your new environment where you are putting the bridge-group on the subinterface, will there be any IP traffic sent in that VLAN? If so it needs an IP address. If no IP traffic in that VLAN then it does not need an IP address.

If that does not sufficiently answer your question then we need some additional clarification of the situation. What kind of traffic will be carried in that VLAN? How do you want it to be forwarded? What happened to the IP traffic that used to be processed on that interface?



New Member

Re: DLSW - NO IP Address - FastEthernet.

Hi Rburts,

Appreciate your super consultation.

You solve my problem.

Yeah, only SNA traffic will be carried in the VLAN for the sub-interface.

Thanks alot.



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