ACL updation on cisco router

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Jun 27th, 2008
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Let say There is a 500 line ACL on a cisco router. And I have to make some changes in the ACL like addition of a new ACL entry somewhere between ACL entries. I copy all the ACL entries in a notepad and edit it. Now when I will do no access-list <acl number> and paste the updated ACL entires on router it will take some time (1 sec,2 sec or 5 sec).

Suppose there is some critical application in my network that is permitted by ACL entry at line 498. Now my concern is whether that application communication would break or new communication can be started or not, until the ACL entry at line 498 is not pasted in router configuration.

And will it make any difference if I use the TFTP server for the same task (editing ACL)?

I believe If we use the TFTP server then it will not affect the application communication. I think TFTP process copy the entire file in running memory and then replace the ACL entries on the router instantaneously (This is just my assumption).

Could someone please clarify how this works and clear my doubts.

Thanks in Advance.


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JORGE RODRIGUEZ Fri, 06/27/2008 - 15:58
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With long acls you can add the nessesary line without going through the process normally done on small access-lists of cutting and pasting updated acl.

See this thread




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