Problem with MAC Pinning and new VLAN

Question

[Cross posting to Nexus 1000V and UCS forums]
Hi all, I have a working setup of UCS 1.4 (3i) and Nexus 1000V 1.4 and as per the best practice guide am using 'channel-group auto mode on mac-pinning' on the Nexus uplinks. I am having trouble when adding a new VLAN into this environment, and it is a reproducable problem across two different installations.
I go through the usual VLAN creating process on the Nexus, the upstream network and within UCS itself. I create the new vethernet port profile and set it as an access port in the new VLAN. However when I attach a VM (either existing or new) to this new vethernet port profile within vCentre the VM cannot communicate with anything. However, if I disable MAC pinning with 'no channel-group auto mode on mac-pinning', the VM instantly starts to talk to the outside world and the new VLAN is up and running. I can then turn MAC pinning back on again and everything continues to work.
So the question is, is this behaviour normal or is there a problem? Disabling MAC pinning does have a brief interruption to the uplink so is not a viable long-term solution for the customer when they want to add new VLANs. Is there a way to add new VLANs in this scenario without any network downtime, however brief?
Thanks

Answer 1

Simon,
Let's gather some further outputs if you're able to recreate this (if this is prod, let me know and I'll whip this up in my lab).
Go through the process of setting up the new VLAN.  Once you confirmed your VM has no connectivity when using a PP tied to the new VLAN, gather the following outputs into a text file and attach to this thread:
From the VSM:
show vlan
show int trunk
show log last 15
module vem x execute vemcmd show vlan y (x = module of VEM where VM is running, y is the VLAN ID)
module vem x execute vemcmd show bd y (y = VLAN ID)
module vem x execute vemcmd show pc
module vem x execute vemcmd show port
module vem x execute vemcmd show pinning
module vem x execute vemcmd show trunk
From the CLI of UCS Interconnect:
connect NXOS
show vlan
show int trunk
Also please highlight or Identify:
- Problem VLAN ID #
- VM veth # in question (1000v)
- vEth # for each Service Profile vNIC used for your VEM uplinks (UCS)
We'll start with this and work from here.   Once I have these outputs I'll let you know if I need anything else.
Regards,
Robert
(I'll keep this as the main thread, and update the 1000v forum once we resolve)