Disabling duplicate-rule check

Towards editing ACLs, you can disable the default restriction on duplicate rules within an ACL. You can then create a duplicate rule at a new sequence before deleting the previous version.

Note

We recommend that after ACL-editing sessions towards which you disabled duplicate-rule check, restore the default setting—by entering the no allow-duplicate-rules command.

Enter configure terminal to access global configuration mode.
```
device# configure terminal
```
Enter acl-policy to access ACL policy mode.
```
device(config)# acl-policy
```

Enter allow-duplicate-rules.

device(config-acl-policy)# allow-duplicate-rules

The following example is a typical editing flow.

Enter the show running-config command to display the rules in the ACL that you need to modify.

device# show running-config mac access-list extended mac1
mac access-list extended mac1
 seq 10 permit host 0001.0001.0001 any
 seq 20 deny host 0001.0001.0002 any count
 seq 30 hard-drop host 0001.0001.0003 any mirror

Enter the allow-duplicate-rules command.

device# configure terminal
device(config)# acl-policy
device(config-acl-policy)# allow-duplicate-rules

In the ACL that you need to modify, create the duplicate rule—specifying the new sequence number—and then delete the old rule.

device(config-acl-policy)# exit
device(config)# mac access-list mac1
device(conf-macl-ext)# seq 11 hard-drop host 0001.0001.0003 any mirror
device(conf-macl-ext)# no seq 30

Enter the no allow-duplicate-rules command to restore the default setting.

device(conf-macl-ext)# exit
device(config)# acl-policy
device(config-acl-policy)# no allow-duplicate-rules