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Priority Mapping Results Are Incorrect

Common Causes

This fault is commonly caused by one of the following:
  • On the outbound interface, packets do not enter queues corresponding to priorities of packets.
  • The priority types trusted by the inbound and outbound interfaces do not meet service requirements.
  • The priority mappings configured in the DiffServ domains bound to the inbound and outbound interfaces do not meet service requirements.
  • There are configurations affecting priority mapping on the inbound and outbound interfaces.

Procedure

  1. Check whether packets enter the correct queues on the outbound interface.

    Run the display qos queue statistics interface interface-type interface-number command to check whether packets enter the correct queues on the outbound interface.

  2. Check whether the priority types trusted by the inbound and outbound interface are correct.

    Run the display this command in the interface view on the inbound or outbound interface to check whether the trusted priority type set using the trust command is correct. (If the trust command is not configured, the system trusts the 802.1p priority in the outer VLAN tag by default.)

    • If not, run the trust command to specify the correct priority type.
    • If so, go to step 3.

  3. Check whether the priority mapping configuration in the DiffServ domain bound to the inbound or outbound interface is correct.

    Run the display this command in the interface view on the inbound or outbound interface to check whether the trust upstream command is configured. If not, the system trusts the DiffServ domain default by default.

    Run the display diffserv domain name domain-name command to check whether the mappings between local priorities and packet priorities are correct.
    Local priorities are assigned to packets on the inbound interface after priority mapping.
    • If the priority mappings are incorrect, run the ip-dscp-outbound, mpls-exp-outbound or 8021p-outbound command to correctly configure the mappings between local priorities and packet priorities.
    • If the priority mappings are correct, go to step 4.

  4. Check whether there are configurations affecting priority mapping on the inbound and outbound interfaces.

    The following configurations affect priority mapping on the inbound and outbound interfaces:
    • If the undo qos phb marking enable command is configured, the system does not perform PHB mapping for outgoing packets on an interface.
    • If the trust upstream none command is configured, the system does not perform PHB mapping for outgoing packets on an interface.
    • If packets match a traffic policy that is applied to the inbound or outbound direction (using the traffic-policy command) and contains a remark 8021p, remark ip-precedence, or remark dscp traffic behavior, the packet priority is re-marked.

    Run the display this command in the interface view on the inbound or outbound interface to check whether there are any configurations affecting priority mapping. If so, delete or modify the configuration as required.

Copyright © Huawei Technologies Co., Ltd.
Copyright © Huawei Technologies Co., Ltd.
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