Layer 3 Etherchannel vs Two Seperate Links

[Patrick McHenry]

   Hi,

We were going to create a 2 port, layer 3 etherchannel between a 1002 router and a 3750X layer 3 core switch. We wanted to create bunled link between them but, now we are going to be putting a Riverbed device between the router and core switch.

Becasue of this, would it be best to abandon the idea of creating a layer 3 etherchannel and just have 2 links from the router and core switch and have traffic load balance between the 2 links?

The Riverbed will have 2 connections into it from the Core switch and 2 connections into it from the 1002 router. I was hoping to keep the layer 3 etherchannel but, do you think it would be best to create 2, /29 nets and have the router/Riverbed and Core Switch/Riverbed load balance.

Thank you.

[Reza Sharifi]

Hi
If the Riverbed supports LACP you can still configure one Etherchannel facing the switch and one facing the router
Most vendors support LACP
HTH

Sent from Cisco Technical Support iPhone App

[Patrick McHenry]

Oh I see. You are saying create the LACP tunnels from the Riverbed to the router and from the Riverbed to the switch.

The Riverbed interfaces that connect to the router and switch have IP addresses though. So, you are saying , create layer 3 etherchannels to the Riverbed? Or, are you saying, create layer 2 etherchannels between the router and Riverbed and layer 2 etherchannels from the switch to the Riverbed. then the layer 3 connectivity will be to between the router and switch?

Thanks, Pat.

[Steve Fuller]

Hi Patrick,

I just took a look through the Riverbed Steelhead deployment guide and I don't see link aggregation as one of the physical in-path deployment options. Additionally there's no mention of LACP with respect to the Steelhead inpath interfaces, but only with respect to the Interceptor product.

FYI, in our environment we use two separate routed links configured as /29 from the WAN router, through the Steelhead and to the LAN. That said we connect the Steelhead to two separate LAN routers and hence a port-channel is not an option in our case.

Regards

[Patrick McHenry]

Thanks - Steve,  That is how we deploy it as well. Is that best practice?

Maybe I should just stick with that design at the new site and forget about the etherchannel thing.

Thanks.

[Steve Fuller]

Hi Patrick,

That is how we deploy it as well. Is that best practice?

Not sure if it's best practice, but it's certainly one of the designs proposed within the Riverbed Steelhead Deployment guide I mentioned above. For us it's a design that works and doesn't introduce any unnecessary complexities.

Regards