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IOS-XE bridge-domain and broadcasts

Hi all.  I have two ISR4321 routers connected and have end to end communication at least from the L3 interfaces of each router (RTR1 and RTR2) to any device on the rest of the network.  Granted I've only tested with icmp.  Nonetheless, broadcast doesn't appear to be allowed/passing, so things like dhcp aren't working coming from RTR1 or RTR2.  Even if I static configure a computer in one of the vlans I'm extending to the RTR1 and RTR2, hang off either, I'm unable to even ping the gateway and Wireshark on the computer just shows constant arp request for who has the gateway.  I attached a diagram of my setup and the config I have for RTR1 and RTR2.  Any advice on how I can configure RTR1 and RTR2 to allow broadcasts to traverse properly?  Thanks. 

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Re: IOS-XE bridge-domain and broadcasts


A link between PRT1 and L2 switch is not configured properly. As you mentioned that it is trunk port but the configuration is not looking as you mentioned in the diagram:

interface GigabitEthernet0/0/0
 no ip address
 negotiation auto

 Please share your L2 switch port configuration so we can guide you more on this port configuration.

Deepak Kumar,
Don't forget to vote and accept the solution If this comment will make help you!

Re: IOS-XE bridge-domain and broadcasts

My apologies, those were the connections for Cisco 1941 routers I want to replace. The interface connecting to the L2 switch is gi0/0/1.  Interface E0/2/0 on each router is for the SHDSL link.  On RTR2 the workstation is on Gi0/1/0. I'll have to update this diagram.


The L2 switch is Brocade.  I'm away from the computer, but the vlans I've configured on the ISRs are in use throughout the LAN on the MLS and other edge switches.  On the L2 switch depicted I have the interface tagged in VLANs 15, 700, and 972 and as a 

spanning-tree 802-1w admin-pt2pt-mac



Re: IOS-XE bridge-domain and broadcasts

I created this post because I had ran into an issue based on one project that I initially posted about.  Below is the other post which has the solution.

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