3com 4500 qos

Posted on 2011-04-30
Last Modified: 2012-08-13

can you help how to apply qos on 3com 4500 switch . i required to set the QOS on vlan 192.168.100.x  port 80  with higher priority .

after looking some tech docs it say dont have to create ACL can apply priority by port any help that would be great

Question by:sandyferdinando
    LVL 26

    Expert Comment

    I don't know 3Com sytax, but here is a link to a command reference for this switch:
    LVL 6

    Accepted Solution

    Hello Sandy,

    You have three steps for QoS - Classification, Marking, and Prioritization (or Queuing). The first two are easily done with ACLs and the queuing is automatically done for marked traffic. It is also important to understand if you are using the 4500 for just switching or for routing as well. If it is just switching, layer 2 marking will resolve what you need easily.

    First, set an ACL to match your traffic

    acl number 3000
    rule permit tcp source . destination destination-port eq 80

    Next, set your Classifier (matches the traffic, to be used for marking later)

    traffic classifier web
    if-match acl 3000

    Now the Marking part (the action to be applied to the traffic), this will mark the 802.1p or layer 2 to 6. You can use DSCP if you want to maerk layer 3.

    traffic behavior mark6
    remark dot1p 6

    Now the policy which ties it all together

    qos policy markweb
    classifier web behavior mark6

    And finally put it on the interface where you expect the incoming traffic

    interface Gigabitethernet x/x/x
    qos apply policy markweb inbound

    The traffic will be marked with 802.1p as 6 and automatically put into the according local-priority Queue. The default 802.1p to local-priority map is as below. You can change it with mapping commands. Higher the number, higher the priority. You can also change the queue methods.

    (802.1p -> local)
    0 -> 2
    1 -> 0
    2 -> 1
    3 -> 3
    4 -> 4
    5 -> 5
    6 -> 6
    7 -> 7

    Good luck!


    LVL 67

    Expert Comment

    This question has been classified as abandoned and is closed as part of the Cleanup Program. See the recommendation for more details.

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