UCS and PVLANs

[Steven Sumichrast]

We have a need to be able to receive a promiscuous mode PVLAN from an upstream Catalyst switch into an existing Cisco UCS Mini chassis.  The chassis is connected to the switch that has the PVLANs on it and is already trunking "normal" VLANs to the UCS Mini.  The Cisco documentation seems to suggest that PVLANs are not supported with the UCS environment at all, but I was wondering if we're mis-interpreting it. 

Is it possible to send down the PVLAN in the existing trunk and just pass the PVLAN straight to the blades OS (in this case ESXi)?  I do not need the UCS to terminate the PVLAN, I just need to get the PVLAN down the trunk.  With a normal FI I wouldn't think this is a huge deal -- I could just land them as a disjoint layer 2 connection on the FI.  However since this is a UCS mini ports are limited.

[Walter Dey]

Hi Steven

http://www.cisco.com/c/en/us/support/docs/servers-unified-computing/ucs-b-series-blade-servers/116310-config-ucs-pvlan-00.html#anc6

PVLAN Implementation in UCS

UCS closely resembles the Nexus 5000/2000 architecture, where the Nexus 5000 is analogous to the UCS 6100 and the Nexus 2000 to the UCS 2104 Fabric Extenders.

Many limitations of PVLAN functionality in UCS are caused by the limitations found in the Nexus 5000/2000 implementation.

Important points to remember are:

• Only isolated ports are supported in UCS. With the N1K incorporated, you can use community VLANs, but the promiscuous port must be on the N1K as well.
• There is no support for promiscuous ports/trunks, community ports/trunks, or isolated trunks.
• Promiscuous ports need to be outside the UCS domain, such as an upstream switch/router or a downstream N1K

[Steven Sumichrast]

Yes, I stated the documentation indicates what you posted.  The issues comes down to the second and third bullet, which states:

There is no support for promiscuous ports/trunks, community ports/trunks, or isolated trunks.

And then it seems to directly contradict itself stating:

Promiscuous ports need to be outside the UCS domain, such as an upstream switch/router or a downstream N1K

So does this mean we can have the Promiscuous PVLAN included on the existing 802.1q trunk from the switch to the UCS FI, create the Primary VLAN for the Promiscuous PVLAN in UCSM, add that to the service profile and then let the downstream ESXi dvSwitch handle that PVLAN?  (dvSwitch will play nicely with Promiscuous mode PVLAN.)

[Walter Dey]

Which UCS version are you using ?

[Steven Sumichrast]

The environments in question are the UCS Mini platform running code 3.0(2e)