2.Cisco ASA Remove Access-List



If you want to remove an access-list from a Cisco ASA Firewall then you’ll find out that removing it doesn’t work the same as on Cisco IOS routers or switches. Let me give you an example of creating an access-list and then try to remove it:

ASA1(config)# access-list MY_ACL permit ip any host 192.168.1.1
ASA1(config)# access-list MY_ACL permit ip any host 192.168.1.2
ASA1(config)# access-list MY_ACL permit ip any host 192.168.1.3
ASA1(config)# show access-list MY_ACL
access-list MY_ACL; 3 elements; name hash: 0x88151b6c
access-list MY_ACL line 1 extended permit ip any host 192.168.1.1 (hitcnt=0) 0x78efec90 
access-list MY_ACL line 2 extended permit ip any host 192.168.1.2 (hitcnt=0) 0x74d90efe 
access-list MY_ACL line 3 extended permit ip any host 192.168.1.3 (hitcnt=0) 0xa4113df3

I just created a simple access-list with a couple of entries. Let’s try to delete it like you would on normal IOS:

ASA1(config)# no access-list MY_ACL
ERROR: % Incomplete command

Using “no” in front of it doesn’t work…the ASA thinks that we want to remove a single entry, not delete the entire access-list. The following command will work:

ASA1(config)# clear configure access-list MY_ACL

Use the clear configure command to get rid of the entire access-list, let’s verify this:

ASA1(config)# show access-list MY_ACL           
ERROR: access-list <MY_ACL> does not exist

That’s it…different command, same result. The clear configure command is not only to remove access-lists but you can use it to remove entire sections from your configuration. Try a “clear configure ?” on your ASA firewall and you will see a huge list with sections that you can remove from your configuration with this command.

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