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RE: Route table growth and hardware limits...talk to the filter
From: "Alex Rubenstein" <alex () corp nac net>
Date: Sun, 9 Sep 2007 09:30:15 -0400
The problem with this is that if you reject the routes initially and then later need them, then they're not in your incoming BRIB to reconsider. BGP is an incremental protocol. You can either save an update or you can ignore it, but if you ignore it, it's just plain gone.
If BGP is an incremental protocol (which of course, I know it is), why doesn't a certain vendor treat it that way? *cough* BGP Scanner *cough*. In any event, if the feature was implemented post-received routes (just like prefix-lists were with soft-reconfig), having a copy of the table that was sent to you by a peer, this would be trivial to do in code. Would it be CPU intensive? Perhaps, but so is having 225k routes and climbing. I'd submit that the CPU burned to do a route lookup on a BGP-RIB when a route is withdrawn or announced to see if something less specific exists would not in fact be that bad -- routing lookups, isn't that what a router is supposed to do? -- Alex Rubenstein, AR97, K2AHR, alex () nac net, latency, Al Reuben Net Access Corporation, 800-NET-ME-36, http://www.nac.net
Current thread:
- Re: Route table growth and hardware limits...talk to the filter, (continued)
- Re: Route table growth and hardware limits...talk to the filter Jon Lewis (Sep 08)
- Re: Route table growth and hardware limits...talk to the filter Forrest (Sep 08)
- Re: Route table growth and hardware limits...talk to the filter Tony Li (Sep 08)
- Re: Route table growth and hardware limits...talk to the filter Randy Bush (Sep 08)
- Re: Route table growth and hardware limits...talk to the filter Adrian Chadd (Sep 09)
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- Re: Route table growth and hardware limits...talk to the filter Randy Bush (Sep 09)
- Re: Route table growth and hardware limits...talk to the filter William Allen Simpson (Sep 09)
- Re: Route table growth and hardware limits...talk to the filter Randy Bush (Sep 09)
- Message not available
- Re: Route table growth and hardware limits...talk to the filter Randy Bush (Sep 09)
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- Re: Route table growth and hardware limits...talk to the filter Randy Bush (Sep 10)
- RE: Route table growth and hardware limits...talk to the filter Alex Rubenstein (Sep 09)
- Re: Route table growth and hardware limits...talk to the filter Mark Tinka (Sep 09)
- Re: Route table growth and hardware limits...talk to the filter randal k (Sep 09)
- Re: Route table growth and hardware limits...talk to the filter Andy Davidson (Sep 09)
- Re: Route table growth and hardware limits...talk to the filter tony sarendal (Sep 09)
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- RE: Route table growth and hardware limits...talk to the filter Church, Charles (Sep 11)
- Re: Route table growth and hardware limits...talk to the filter Kevin Oberman (Sep 12)
- Re: Route table growth and hardware limits...talk to the filter Matt Liotta (Sep 20)
- Re: Route table growth and hardware limits...talk to the filter Jon Lewis (Sep 20)
- Re: Route table growth and hardware limits...talk to the filter Bora Akyol (Sep 20)