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How to send specific routing update?

Sam Halabi said:

The preceding access list will permit,,,, and so on.

To restrict the update to only, you have to use an extended access list of this


access-list access-list-number {deny | permit} protocol source sourcewildcard

destination destination-wildcard | mask mask-wildcard

This defines an extended access list that matches on a source destination or a source mask

tuple to permit or deny a specific routing update. The access list number falls between 100

and 199. In the case where the protocol is IP and you are checking on a source/mask tuple,

this would translate into the following:

access-list access-list-number permit ip network-number network-do-notcare-

bits mask mask-do-not-care-bits

For example:

access-list 101 permit ip

A 0 is an exact match bit, and a 1 is a do-not-care bit.

The preceding extended access list indicates that aggregate is to be sent only

because you have indicated that the mask should match exactly. An update of the

form will not be allowed.

You could also accomplish this a couple of other ways. For example:

access-list 101 permit ip host host

Or you could use a prefix list:

ip prefix-list 1 seq 5 permit

I test it on my 2600.And extend access-list is fail.Prefix-list is success.

For extend access-list,I don't understand what's mean of

If I want to send,do I need code or


Re: How to send specific routing update?

Yes, for the extended acl should look like,

access-list 100 permit ip

and for, it should be recoded as

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