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New Member

Access List size?

Are there guidelines/recommendations for the maximum number of items in an access control list in a given family of routers?

Looking for input on various groups (1600-1800; 2500-2600; 3600-3700), if available, so we can do some custom ACLs and make sure the ACL doesn't over-burden the CPU.

Thanks in advance.


Re: Access List size?


There is no as such limit for ACLs.... It is all depends on you environment and you have to check with your traffic and have to check how many of them has hits and drops (matches) in ACLs....

As you told ACL is cpu intensive just becz all the traffic on the applied interface and in applied direction is going to check with ACLs....

Rate if it does,


New Member

Re: Access List size?

I concur there is no practical size and that environment can vary widely from install to install. We are trying to determine if an application we are generating, feeding an ACL with dynamic information, will be impractical for a given series of router.

My question relates to the following scenario:

Large ACL in place (example 500 lines). Would this be impractical for the CPU of a smaller-family router (800 series, 1600/1700 series) to handle?

Second example, 1500 lines would this be impractial for the CPU of a 2x00 series? 3x00 series?

Thank you.

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