Filter and Force DSCP Values (IPv4 ACLs)

In IPv4 extended ACL rules, re-marking (forcing) DSCP values can change the priority on egress traffic, by which you can prioritize ingress traffic.

You can also filter IPv4 packets by DSCP value.

Create or access the ACL.

device(config)# ip access-list extended extd_ACL5

To filter incoming or outgoing packets by DSCP value, define permit or deny rules specifying the dscp parameters.

device(config-ipacl-ext)# seq 5 deny tcp host 10.24.26.145 any dscp 25
device(config-ipacl-ext)# seq 15 permit tcp 10.24.26.146 any dscp 20

To re-mark the DSCP value of incoming packets, define permit rules specifying the dscp-force parameters.
```
device(config-ipacl-ext)# seq 25 permit tcp 10.24.26.147 any dscp-force 10
```

Apply the ACL to the appropriate interface.

device(config)# interface ethernet 2/2
device(conf-if-eth-2/2)# ip access-group extd_ACL5 in