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Latest post 05-29-2009 7:32 AM by nydimka23. 1 replies.
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  • 05-29-2009 7:24 AM

    Task 10.65 Catalyst 3550 Per-Port Per-Vlan Classification

    In the task we are asked to mark IPX traffic with CoS value of 2 on interface connecting to R4.  That particular interface has been converted to trunk (in previous task) ... now i have configured 2 layerd class-maps as the solution guide but instead of setting IPX traffic to DSCP (like SG has) i set it to CoS 2 ... In the SG it has a note that we cannot set that traffic with CoS value (only when trusting DSCP) .. i thought that you can set the CoS value if the interface is a trunk ...

    Can anyone clarrify this for me please? Why we can't use set cos command in class-map, is it becuase we have to trust DSCP? then would adding trust DSCP in policy-map make it work?

    class-map match-all VLAN_146_ICMP
      match vlan  146
      match class-map ICMP

    class-map match-all VLAN_146_IPX
      match vlan  146
      match class-map IPX

    policy-map PER_PORT_PER_VLAN
      class VLAN_146_ICMP
       set dscp cs3
      class VLAN_146_IPX
       set cos 2
        trust dscp

    Dmitriy Litvinko, CCIE #25150 (R&S)

    • Post Points: 5
  • 05-29-2009 7:32 AM In reply to

    Re: Task 10.65 Catalyst 3550 Per-Port Per-Vlan Classification

    may be this quesiton will be simpler ....

    If we need to set CoS value for specific traffic and we are using class-maps, then we cannot set cos directy, therefor we have to use DSCP vlaue (by checking with cos-dscp maping table) .... is this accurate?

    nydimka23:

    In the task we are asked to mark IPX traffic with CoS value of 2 on interface connecting to R4.  That particular interface has been converted to trunk (in previous task) ... now i have configured 2 layerd class-maps as the solution guide but instead of setting IPX traffic to DSCP (like SG has) i set it to CoS 2 ... In the SG it has a note that we cannot set that traffic with CoS value (only when trusting DSCP) .. i thought that you can set the CoS value if the interface is a trunk ...

    Can anyone clarrify this for me please? Why we can't use set cos command in class-map, is it becuase we have to trust DSCP? then would adding trust DSCP in policy-map make it work?

    class-map match-all VLAN_146_ICMP
      match vlan  146
      match class-map ICMP

    class-map match-all VLAN_146_IPX
      match vlan  146
      match class-map IPX

    policy-map PER_PORT_PER_VLAN
      class VLAN_146_ICMP
       set dscp cs3
      class VLAN_146_IPX
       set cos 2
        trust dscp

    Dmitriy Litvinko, CCIE #25150 (R&S)

    • Post Points: 5
Page 1 of 1 (2 items)
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