OSPF - QoS/CoS Marking

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Hi All. 
I'm just wiresharking some OSPF traffic to check QoS markings and I notice that OSPF hellos generated by our Summit X460 are marked as DSCP CS6 but tagged as 802.1p priority 7.
We've got no QoS re-marking configured on the switch.
Can anyone explain the discrepancy and why the device doesn't use 1 to 1 class marking?
Many thanks....
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Stephen Elliott

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Posted 4 years ago

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Paul Russo, Alum

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Hello Stephen

If you do a show <VLAN name> do see a qosprofile assigned to that VLAN?

Thanks
P
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Stephen Elliott

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thanks for your reply Paul.

extract from a 'show vlan <name>'....

"QosProfile:                      None configured"
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simon bingham

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 DSCP CS6 is a layer 3 marking 
 802.1p priority 7. is a Layer 2 Marking 
as they are different methods there is no defacto requirement  for them to match.
Simon Bingham ( alternative networks  )
 
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Stephen Elliott

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Yes of course,  thanks Simon.  I understand that but, in the absence of a QoS policy, I thought it was standard practice to mark CoS the same as the DSCP CS.
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simon bingham

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802.1p 7 is called Network Control so that would make sense and CS6 is the same value used by Cisco for protocol traffic so that might be why the values don't match. But as said I don't think they have to.