cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
359
Views
0
Helpful
3
Replies

cos and dscp

carl_townshend
Spotlight
Spotlight

Hi all, If I get my switch to mark the cos values from a specific vlan, when this traffic then moves to the next switch, if I dont set the uplink to trust these frames, what will happen will the frame still keep its marking?

3 Replies 3

Mark Yeates
Level 7
Level 7

If you don't configure the trust on the interface the cos value will be changed to back to zero.

HTH,

Mark

m-haddad
Level 5
Level 5

What mark has said is correct unless the next switch doesn't have mls qos enabled (Globaly). Then the QoS marking will stay and will be forwarded.

If your ip phones (Avaya in our case) are marking the voice packets such as dscp 46 and call control af31 and you have your cos-dscp map set correctly is it best to trust cos of dscp on the trunks between layer 2 switches? What about the trunk interface on the switch connecting to a router?

Thanks

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: