Editing access lists line by line on Cisco routers

If you're using number access lists there is a really easy way to edit the access lists line by line on your router without having to remove and add the whole access list each time. Note: This feature is not available on older versions of IOS.

Router#conf t
Router(config)#ip access-list ext

Now you are in access list editing mode. To get a quick look at your access lists:

Router(config-ext-nacl)#do show access-list

Output will look similar to the following:
10 permit tcp any host 192.168.1.1 established log
20 permit udp any host 192.168.1.1
30 permit ip host 10.10.10.10 host 192.168.250.250

Note the numbers next to each line for each access list. To remove one of the lines on your access list just type:

Router(config-ext-nacl)#no

You can also add a line to your access list. To insert a line between lines 20 and 30 above, just start your new line with 25 (or any other number between 20 and 30):

Router(config-ext-nacl)#25 permit udp any host 192.168.200.100