BGP network statement

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Feb 12th, 2009
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All,


If I have three interfaces:


int lo1

ip address 172.5.5.5 255.255.255.255


int fa0/0

ip address 192.168.1.1 255.255.255.0


int s1/0

ip address 10.5.5.1 255.255.255.252



Would my network statements in BGP for s1/0 and lo1 look like:


network 10.5.5.0 mask 255.255.255.252

network 172.5.5.5 mask 255.255.255.255

network 192.168.1.0 mask 255.255.255.0


In other words, my masks in bgp should match what's on my interface, right? I know there's exceptions to the rule.



Thanks!

John

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Edison Ortiz Thu, 02/12/2009 - 10:18
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Yes, it must match the mask in the routing table.


__


Edison.

Richard Burts Thu, 02/12/2009 - 10:20
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John


When you use the mask in the BGP network statement then BGP looks into the routing table for a prefix with exactly that mask. So you your BGP mask should match what in on your interface.


HTH


Rick

Harold Ritter Thu, 02/12/2009 - 10:26
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John,


That is correct. By the way, the mask configured on the network statement for 192.168.1.0 is the default maks for a class C prefix and will therefore not show in the config.


Regards

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