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VLAN Bridging over a routed T1 Link

I have a HP 9304 Routing Switch and a Cisco 7206 Router connected by their Fast Ethernet ports using VLAN2 & VLAN7 to subinterface F0/0.2 & F0/0.7 (dot1q) configurations. Both VLANs communicate between the two devices. The HP 9304 is on Image version 6.628T43 and Boot version 7.01.08. The Cisco 7206 is running IOS 12.1 and there are 11 remote sites connected through it.

One of the remote sites (CHM) has a HP4000 switch on subnet 10.18 routed through a Cisco 2650 (IOS 12.1) to this Cisco 7206. This (CHM) is the only site in my new wireless network that is serially connected. The remaining Wireless network sites are all (VLAN7) switched to the HP 9304 through HP4000 switches over single mode fiber. VLAN7 routing occurs in the HP9304 Routing Switch.

I must push this Wireless VLAN7 out to the CHM site through the Cisco 7206, over the T1 line, to the Cisco 2650, and into a single (VLAN7) port in the HP 4000 switch. A wireless Access Point connects to this port. The HP4000 switch and port are configured for VLAN7 and the default VLAN and both devices communicate on the respective VLANs.

We have found no way to (both) continue to route to the existing subnet (10.18) and to bridge the new Wireless VLAN7 over the serial WAN link. This was the subject of several Cisco TAC cases (B811245, B912505, C247198). There was no resolution. Even with a Cisco engineer on site, we could not route and bridge on the same serial (T1) WAN link. Expanding this wireless infrastructure to other existing sites will present the same issues and we must solve this problem.

In light of the following restrictions, how can this be accomplished? The end users are Police officers in patrol cars that drive into these sites to connect to our VLAN7 subnet over wireless access points (802.11b). They must not have to reboot nor reconfigure the notebook PC upon entering/leaving the sites. The notebooks use DHCP and, except for this one site, everything works great. Changing hardware brands is not an immediate solution - budgeting issues!).

Any help will be greatly appreciated.


Re: VLAN Bridging over a routed T1 Link


The only way I can think of getting this to work is to bridge the traffic and not route between the locations and VLAN7. Essentially, bridge VLAN7 all the way back to the 7206 serial interface. On the 7206 side use IRB so you can bring the bridged traffic into a BVI so it can be routed between the rest of your networks.

Another possible solution is Mobile IP perhaps but I'm not sure if the HP box supports this.

Hope this gives you gives some more ideas...

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