N5548 - vPC - noOperMem

[NaelShahid_2]

When creating the a vPC on a pair of N5548UP’s how should the channel group mode be set when connecting to a Emulex CNA with the ports attached to a the N1K?

I have configured the mode as “active”, however, when the server is booted and the physical ports come up the channel group is operationally down stating no operational members. I am sure this is due to no lacp negotiation on the trunk. Please note the server does not have ESXi or the N1KV installed as yet, I am in the process of configuring boot from SAN. I am wondering if the trunk would come up once the N1KV was installed with “channel-group x mode active”, however, where does this put me while the system is booting and attempting to access the FC storage.?

Please correct me if I am on the wrong track....

[Prashanth Krishnappa]

Since you do not have any OS on the server yet, it cannot send LACP frames and hence your port-channel will not come up and vFC associated with the port-channel will not come up either. You have couple options

1)Do not use LACP channel. Use individual interfaces or ON mode channel

2)If you are running 5.1(3)N1(1) and later on your Nexus 5548, you have an option of binding vFC to physical ethernet. In older NX-OS you did not have this option once the physical ethernet is in a port-channel.

[NaelShahid_2]

Great, thanks for the response. I thought this would be the case, however, I thought that if using a port channel with the N1Kv the mode NEEDED to be “active”.... Obviously I was incorrect here. I will use mode “on” as I require the use of a port channel.

In an environment in which you boot from san via a CNA then the vPC must always be a configured as a static port channel (mode on)?? If using LACP and no LACP PDUs are received by the N5Ks is it not the case that the port channel is disabled and the member ports act as individual ports? If this was the case could the fcoe would still boot from SAN then the vPC would come up once the N1K was loaded on the hosts??????

[Prashanth Krishnappa · Accepted solution]

You can use active(LACP) but you will need to run NX-OS 5.1(3)N1(1) or later to get the capability of binding vFC to

individidual interface when configured for port-channel/vPC.

http://www.cisco.com/en/US/docs/switches/datacenter/nexus5000/sw/release/notes/Rel_5_1_3_N1_1/Nexus5000_Release_Notes_5_1_3_N1.html#wp384490

[NaelShahid_2]

great, thanks again