How to block traffic originating from a router?

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Mar 18th, 2007
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I know that ACLs cannot do this. I think I remember reading somewhere in my BSCI studies of a technique to do this. Is the only way to do this to use passive interfaces or distribute lists for redistribution?


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royalblues Sun, 03/18/2007 - 06:06
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Distribute lists are used to block routing updates sent over a specific interface. You can use these lists to advertise certain prefixes to the neighbor. The adjaceny between the neighbors is still maintained.

Passive interfaces on the other work a bit differently. When used in EIGRP & OSPF, they do not send hello packets nor listen to them and hence adjacencies cannot be formed.

RIP on the other hand continues to listen to updates on the passive interface.

HTH, rate if it does


paolo bevilacqua Sun, 03/18/2007 - 09:17
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Can you better specify what kind of traffic are you talking about ? Routing updates, traffic that is sourced from withing the router, voice or what ?


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