ESX Etherchannels to 2148s

[mflanigan]

My customer has 2 N5ks and 4 2148s.  The N5ks have VPC between them, and the 2148s are single-homed, 2 to each N5K.  Am I corect in saying that an ESX box with a 4GB host etherchannel would have one connection to each 2148, and that the ports would be configured in a chennel-group on each N5K, and in a VPC instance between the 5Ks?

Thankls

[Lucien Avramov]

Your answer is here:

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9670/configuration_guide_c07-543563.html

Look at figure 1 and figure 2.

[mflanigan]

Lucien,

Thank you for your response.  I am familiar with the doc you ponted me to.  My question was, since the doc only shows a single connection to each of the N5Ks, I wanted to be sure that if I had 4 server connections in a channel, that I could home one connection to each of 4 2148s, then home 2 of the 2148s to each N5K, and define a channel group on each N5K with 2 members in the group, then put the port channel in a vpc to get 4GB total.  I know the 2148s can only have a single connection each, but I was hoping the N5Ks could aggregate them.  The config would look like this:

int eth 100/1/1            First 2148

channel-group 10

int eth 101/1               Second 2148

channel-group 10

int port-channel 10      N5K VPC to peer with identical config

vpc 10

I think as long as there is only 1 link per 2148, I'm OK, but I want to be sure, due to the rather sevre limitations imposed by the 2148s.

Regards,

Mike Flanigan

[Lucien Avramov]

Mike, that will be a no go. your first pair of N5K vpc would need to have a vpc peer link with the other pair of N5K vpc to communicate and avoid loops and this is not possible.

4 FEXs going to only 2 N5K wont work either and that's a FEX limitation.

The 2248 will support multiple ports to one server so you will be able to have 2 times 2 links to 2 fexs.

Please support CSC Helps Haiti

https://supportforums.cisco.com/docs/DOC-8895

https://supportforums.cisco.com

[mflanigan]

Lucien,

Thanks again.  I believe I understand your answer - I'll need to get with the custimer.  Am I right then in saying that the ESX vswitch could be configured to support 2 2GB channels,instead of a single 4GB channel, each channel with a single connection to a 2148?  That is in accordance with the diagrams.  The 2148s would see the 2 ESX channels as separate hosts.  Can you confirm this?

Thanks

Regards,

Mike Flanigan

[Lucien Avramov · Accepted solution]

Well, in this case, I would preferably suggest you to even use the Nexus 1000v if you want to scale with all the vm's.

Otherwise the vswitch is fine too.

Under vswitch, bundle the 2 uplinks together (port-channel).

And physically have one to each FEX, that is how VPC will work.

[mflanigan]

Lucien,

Many thanks, I will proceed along these lines.  Not in a position to do 1000v yet, but I understand the idea.