mls qos command

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Apr 15th, 2010
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If switches do not have the mls qos command what happens to incoming packets that have a DSCP or CoS value configured?  Do they get reset?

Also, if a switch does have mls qos command, but an interface is not set to trust DSCP or CoS, will any marking get reset?


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Jon Marshall Thu, 04/15/2010 - 14:59
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Because QOS is quite different between Catalyst platforms the best thing to do is look at the default configuration for each switch to answer your question eg.

3560 -

3560 default configuration

6500 -

6500 default configuration

For others you can get to the configuration docs from the cisco homepage -> Products & Services -> Switches -> switch you are interested in and then select the configuration docs.


LucaSalvatore_2 Thu, 04/15/2010 - 15:08
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Thanks i'll have a read.... This questions is relevent to 3560 switches.

mohamed zafar Fri, 04/16/2010 - 04:38
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to enable qos on a switch u must enter mls qos

if the it is cos trust it will remark it will take the trusted value


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