38 messages in net.nether.puck.cisco-nsp[c-nsp] VLSM
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ShaunJan 10, 2005 4:53 pm 
Gert DoeringJan 10, 2005 5:26 pm 
Stephen J. WilcoxJan 10, 2005 5:27 pm 
matthew zeierJan 10, 2005 5:46 pm 
ShaunJan 10, 2005 6:19 pm 
Michael SmithJan 10, 2005 6:26 pm 
Stephen J. WilcoxJan 10, 2005 6:28 pm 
lis...@hojmark.orgJan 10, 2005 6:55 pm 
Brant I. StevensJan 10, 2005 11:25 pm 
Gert DoeringJan 11, 2005 2:33 am 
Stephen J. WilcoxJan 11, 2005 6:11 am 
Mark PersikoJan 11, 2005 10:49 am 
Gert DoeringJan 11, 2005 11:22 am 
Hudson Delbert J Contr 61 CS/SCBNJan 11, 2005 12:11 pm 
Brant I. StevensJan 11, 2005 12:45 pm 
Pete TemplinJan 11, 2005 12:52 pm 
Stephen J. WilcoxJan 11, 2005 1:30 pm 
Stephen J. WilcoxJan 11, 2005 1:39 pm 
Pete TemplinJan 11, 2005 2:09 pm 
Gert DoeringJan 11, 2005 2:47 pm 
Gert DoeringJan 11, 2005 2:48 pm 
matthew zeierJan 11, 2005 3:09 pm 
lis...@hojmark.orgJan 11, 2005 5:22 pm 
Anson RinesmithJan 11, 2005 5:47 pm 
Michael LoftisJan 11, 2005 5:57 pm 
Stephen J. WilcoxJan 11, 2005 7:23 pm 
Stephen J. WilcoxJan 11, 2005 7:37 pm 
ShaunJan 11, 2005 8:31 pm 
Jon LewisJan 11, 2005 9:48 pm 
Majid FaridJan 12, 2005 12:24 am 
matthew zeierJan 12, 2005 1:23 am 
Ted MittelstaedtJan 12, 2005 1:41 am 
Ted MittelstaedtJan 12, 2005 1:44 am 
Ted MittelstaedtJan 12, 2005 1:51 am 
lis...@hojmark.orgJan 12, 2005 1:18 pm 
lis...@hojmark.orgJan 12, 2005 1:30 pm 
ShaunJan 13, 2005 4:05 am 
Ted MittelstaedtJan 14, 2005 12:29 am 
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Subject:[c-nsp] VLSMActions...
From:Gert Doering (ge@greenie.muc.de)
Date:Jan 11, 2005 11:22:04 am
List:net.nether.puck.cisco-nsp

Hi,

On Tue, Jan 11, 2005 at 08:49:53AM -0700, Mark Persiko wrote:

If you have a hierarchical network topology with the gateway of last resort facing one egress point at the core, then I've noticed that "ip classless" has the unfortunate side effect of sending all traffic out that egress pipe, whose destination is for subnets that aren't used within the network. That is my condition right now and I am burning bandwidth, and seeking a solution!

Insert local null routes for network that you know you're authoritative for.

In other words, if you are using 172.16.1/24 and 172.16.2/24, and you have packets headed for 172.16.3/24, "ip classless" will make them head to the gateway of last resort instead of just dropping them.

ip route 172.16.0.0 255.255.0.0 null0

One solution I've considered is explicit static routing for all valid subnets of 172.16 and then null routing anything else for 172.16/16 itself. What do you think?

Static routes for the subnets are not needed - more specific route wins anyway, even if you have an overlapping null route.

gert

-- USENET is *not* the non-clickable part of WWW! //www.muc.de/~gert/ Gert Doering - Munich, Germany ge@greenie.muc.de fax: +49-89-35655025 ge@net.informatik.tu-muenchen.de