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Is Cisco UCS tagging frames with "EF"

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dudecrush

IS-IT--Management
Apr 2, 2007
468
US
All - This might be more of a network question, but I thought I'd start here.

The question: Does Cisco UCS - or it's own endpoints - mark it's traffic with Expedited Forwarding by default, or is that done only on the network equipment? I think that I've answered my own question, and that is Yes - UCS does mark it's own traffic.

The backstory: I'm in the process of moving our UCS VM-Host from an old HP to a Cisco fabric extender switch, off a Nexus 9k. We've got a QoS service policy on our network for VoIP traffic. I can't add the QoS service policies to the 9k, which could muck up the migration.

A ticket was opened with Cisco, and they said: "Cisco said + N9K doesn’t change any UCS/Endpoint’s QOS DSCP value by default. E.g. [highlight #FCE94F]If[/highlight] endpoint marks the traffic with EF (DSCP 46, IP precedence 5). N9K will pass the traffic as EF."

So - the key word there is [highlight #FCE94F]"IF"[/highlight]. Given that there is no question mark at the end of that sentence, I'm thinking what they meant was, "When endpoint marks the traffic". The access-layer equipment in-between already has QoS policies on the switchport, so I think they're already tagging. If that's the case, the Nexus 9k will just forward on the traffic with the tagging intact.

Does anyone off-hand if I'm right or totally wrong?
 
Not entirely sure about the UCS itself but CM tags its packets.

Certifications:
A+
Network+
CCENT
CCNA Voice
TVOICE
CAPPS
CIPTV1
CIPTV2
 
Cant you do a copy of the vm and test it first in an isolated place instead of switch and let's hope the best of it?
 
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