vNIC failover testing

Unanswered Question
Apr 5th, 2012

Is there a way to test vNIC or hba failover on an individual blade.  I don't want to have to turn a fabric interconnect off to validate that I have setup a vNIC or hba appropriately on a single blade so is there anyway from the Fabric Interconnect cli to disable a vNIC / hba or force it to failover to the other fabric?

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
colin.lynch Thu, 04/05/2012 - 09:05

Unfortunatley not, would be nice to be able to do a "Shut" on a veth in NXOS mode but you can't (not yet anyway.)

The best way I have found to test blade failover with MINIMAL disruption is to pull the FEX - FI link out, that that blade Pins to. THIS CAN EFFECT other blades depending on your setup.

I.e. if you only have a single FEX link obviously all your blades will be using it.

Best scenario is to use 4 FEX links (If using Gen 1 kit, with discrete pinning) then if you have a full chassis of half width blades you will have  2 servers pinned to each uplink. i.e. 1/5 to link 1, 2/6 to Link 2, 3/7 to link 3 and Blades 4/8 to link 4.

So if you pull FEX link one on FEX A out in the above scenario, all vNICS mapped to Fabric A will failover (if configured to do so) on blades 1 and 5.

Not ideal but better and much quicker than failing a whole FI as you were thinking about.

Obviously the above will not work if you have port-channelled the FEX - FI links.



David McFarland Thu, 04/05/2012 - 10:13

You can test fibre channel failures by putting one of the vHBA's into another VSAN. This will break the zoning for that vHBA. You can just create a dummy VSAN if you don't have one to put it into. This will test your multipathing to the target. vfc's will not failover like a veth will on loss of connection or FI.

There are requests to be able to shut/no-shut a vif, but, nothing so far.


Robert Burns Thu, 04/05/2012 - 10:15

Just to add to Dave's preferred method - changing a VSAN on a vHBA does not require a re-ack of the compute node.  Same concept as modifying VLANs on a vNIC.


christopher.atk... Sun, 04/08/2012 - 09:28

I believe if you reset the DCE interface it will induce FF. You would do that from the equipment tab.

Sent from Cisco Technical Support iPad App


This Discussion