Filtering and forcing PCP values (L2 ACLs)

In Layer 2 extended ACL rules, re-marking (forcing) PCP values can change priority on ingress traffic. You can also filter ingress and egress Layer 2 packets by PCP value.

1. Enter configure to access global configuration mode.
   

   device# configure
   

2. Enter the mac access-list extended command to create or access the ACL.
   

   device(config)# mac access-list extended mac_ac12
   

3. To filter incoming or outgoing packets by PCP value, define permit and deny rules specifying the pcp parameters.
   

   device(conf-macl-ext)# seq 5 permit host 0022.3333.4444 host 0022.3333.5555 pcp 2
   device(conf-macl-ext)# deny host 0022.3333.7777 host 0022.3333.6666 pcp 5
   

4. To re-mark the PCP value of incoming packets, define permit rules specifying the pcp-force parameters.
   

   device(conf-macl-ext)# seq 10 permit host 0022.3333.4445 host 0022.3333.5556 pcp-force 2
   

5. Apply the ACL to the appropriate interface.
   

   device(config)# interface ethernet 0/1
   device(conf-if-eth-0/1)# mac access-group mac_acl2 in