VLAN Load Balancing/Etherchanneling

[wayne.goulden]

I have two data centres located around 10 miles apart. Each data centre has two 6500's for resilience. The data centres are connected via two 1Gbps trunks. I'd like to connect a trunk to each 6500 and either aggregate the links via etherchannel or provide some form of VLAN load balancing so both links are utilised. Using single 6500's is easy, but can it be done across two at each site. The trunks are purely L2 as devices at each site need to be in the same subnet. Any help is appreciated.

Thanks,

Wayne G.

Network Engineer

[jrahm]

I don't think Cisco supports diverse chassis etherchannel, anyone able to make this happen, send details my way!

Since the trunks are pure L2, spanning-tree will make one of the two trunks useless by default for each vlan, but you can tune stp to favor one trunk over the other per vlan. This isn't packet or even flow based load balancing, but it will at least ensure that both trunks carry some data and that not everyone will go for coffee when there is a single trunk failure :-)