QoS Tagging

Unanswered Question
May 8th, 2009
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Would it be possible that a QoS tagging is lost as it traverses between directly connected interfaces of two switches.

What possible reason a dscp marking is stripped on the ingress interface?


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Overall Rating: 4 (2 ratings)
Collin Clark Fri, 05/08/2009 - 08:01
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The only way I can think of is if you remapped the markings, which I don't think is possible ingress on a layer 2 switch.

If you have "mls qos" enabled - BUT you want to keep the DSCP value in the IP header and NOT have the switch re-write it according to it's internal DSCP mapping tables then configure:-

"no mls qos rewrite ip dscp"

By default a switch WILL re-write and DSCP/COS values unless told not to.


bolshoi.88 Sat, 05/09/2009 - 02:16
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Thanks guys. Would there be service interruptions when you apply this commands?


bolshoi.88 Mon, 05/11/2009 - 07:59
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Can this applied to a Cisco 4500?

Any equivalent command?

Thank you.

bolshoi.88 Mon, 05/11/2009 - 08:01
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Is this the same as no qos rewrite ip dscp?

thank you.


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