Why do I need an active uplink to use an appliance port?

Reader Peter sent the following question as a comment to my Direct Attach Appliance Ports post.

When I connected my NAS to use the appliance port, in order for the vnic of the blade server to communicate with the NAS, i found that there should be a connected uplink port in the 6100 even though I created a private VLAN for the appliance port and the vnic. Why?

I thought the topic would make for a nice brief post explaining the Network Control policy and its effect on Service Profile vNIC objects.

By default, all vNIC configurations use a Network Control Policy called “default” which is created automatically by UCS Manager.

The policy specifies that CDP frames are not delivered to any vNIC using this policy, and that if no uplinks are available, that the vNIC should be brought down.

In Peter’s case, since there were no uplinks available, his vNIC is kept down keeping him from using the appliance connected to the Fabric Interconnect.

If we change the policy to instead to Warning, the vNIC will be kept up (though a system warning will be generated) even when there are no available uplinks.   Note that this effectively disables the Fabric Failover feature on any vNIC using this policy.

If you have some interfaces that you want to stay up even when there are no available uplinks, create a policy with this setting and then specify it in the vNIC configuration.  Alternatively, if you want the default behavior of all vNICs (unless specifically configured) to be that they stay up even when no uplinks are available, you can modify the “default” policy as shown here.

10 thoughts on “Why do I need an active uplink to use an appliance port?”

  1. I have made port 20 on each 6120 an Appliance Ports.
    Each port is assigned to a VLAN made under the Appliances tab.

    Cannot seem to make a PIN group using these Appliance ports. They are not a option.

    Is there something I am missing?

    See image here: http://realworlducs.com/wp-content/uploads/2011/11/AppliancePorts.png

    Are the steps to create a vNIC bound to an Appliance Port basically:

    Turn on Ports use as Appliance Ports
    Make PIN Group through Appliance Ports (this will only be one port per FI, I am guess Port-Channels can be used if NAS supports that?)
    Make VLAN internal to UCS
    Make vNIC Template and use newly created VLAN and PIN Group

    Boom!? Should work right?


    1. Pin groups are used to force vNICs (or vHBAs) to use a particular uplink for their non-local (really, unlearned unicast or broadcast) traffic. Since an appliance port will learn the MACs the exist beyond it, no pin group is necessary. Just make sure your vNIC is on the same VLAN and you should be good to go.

  2. Thanks! But when I create a vNIC don’t see the VLAN’s created under the Appliance tab. only those made global or per FI outside of the Appliance tab.


  3. VLAN’s created under the LAN tab (not the Appliances tab) show up when creating a vNIC template.

    But the VLAN’s under the Appliances tab don’t show up when creating a vNIC template.

    I can create an Appliance port (port 20), and a VLAN (MSStorageServer) under the Appliance tab. I can assign that VLAN to the Appliance port.

    But don’t see a way to bind a vNIC to the (MSStorageServer) VLAN. New vNIC templates only see VLANs created under the LAN tab.

    Not sure how to bind a vNIC to the Appliance port VLAN???

    Thanks for you help!


  4. Found that I could give them the same VLAN ID, but not name. That seems to hose things. Go Figure. Thanks for all the help will test this out in the morning.


  5. Testing has been poo so far today.

    Have been hacking at this a while and not getting Appliance ports to work.

    VLAN’s made under the “Appliances” tab are only seen by Appliance Ports. But the VLAN’s under Appliances are not availble to vNIC’s.

    Have heard from a few sources that two VLAN’s with the same VLAN ID are need under the Appliances and LAN tab.

    Have done that, and blades can ping each other, but not the NAS device. Also the NAS device cannot ping the blades.


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