cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
322
Views
5
Helpful
4
Replies

Different MAC-addresses on vlan on C6503 MSFC

t.hadarson
Level 1
Level 1

I have a problem setting different mac-addresses on vlan interfaces in the MSFC. When i change the mac-adress on one vlan interface all vlan interfaces get the same mac. I have done this on some other 6509 with sup1 without any problems. This wouldn't been a problem in normal, but.....

I use one 6503 as BGP-router in a multihomed env.

One separate vlan to each upstream-provider with different /30 nets for the link. Between the catalyst and the provider I have a transparent filter/packetshaper with incoming and outgoing interfaces. On the filter I can group interfaces to belong to the same vlan, but when I group this interfaces the packetshaper stop forwarding because it doesn't know which interface to forward to because the mac-address is the same for different ip-addresses.

I know It's hard to explain this matter in text, but if anyone know anything about how to fix I would appreciate it.

4 Replies 4

tsettle
Level 3
Level 3

From your description I assume you have a sup2/msfc2 system. This issue is documented in the release notes under MSFC restrictions:

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat6000/relnotes/ol_2309.htm

"With a PFC2, if you enter the mac mac_address interface command, the configured MAC address is used for all VLAN interfaces. "

Thank you for the answer.

And yes it's a sup2/msfc2.

Do you think it's possible to do a workaround with HSRP on one vlan, whitout having a second router interface, to get the virtual mac-address of HSRP to assign to the vlan, and set update-source in BGP for that neighbor to the virtual ip-address of HSRP.

Nope--BGP won't work in this situation. You could source from a loopback on the same router, but I don't think BGP's going to allow you to source and terminate a TCP session on an HSRP address. You could try setting up an alias command, using a local ip address, with a difference MAC address, but I don't know that it's going to help you get your traffic shipped to a different IP address through BGP.

Russ.W

Thanks,

I think I'll buy another 6503 for the second upstream provider. (Less problem)

Thanks again for the help.

Case closed

Tony

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: