PSI/Digex announcements

Thu Nov 11 22:26:52 UTC 1999

Joe,

Yes - this is indeed not optimal. To keep routing tables manageable, BGP
announcements should be aggregated into a shorter prefix such as /20 or /19
(whatever is possible). Many autonomous systems accidentally leak longer
announcements for various reasons; accurate filtering can eliminate these
mistakes. It looks like the autonomous system from your email is
redistributing connected routes - you can start by contacting the
originating autonomous system. 

Hope this helps.

CF  

-----Original Message-----
From: Joe Shaw [mailto:jshaw at insync.net]
Sent: Thursday, November 11, 1999 3:58 PM
To: nanog at merit.edu
Subject: PSI/Digex announcements

I have a non peering T1 to PSI for VPN customers.  While troubleshooting
some problems for one of those VPN customers I came across these:

HOUSTON_BR1#show ip bgp regex ^174$

   Network            Next Hop            Metric LocPrf Weight Path
*> 12.15.224.192/27   38.7.128.1                           200 174 i
*> 154.32.255.0/30    38.7.128.1                           200 174 i
*> 192.245.179.248/30 38.7.128.1                           200 174 i
*> 198.17.203.0/25    38.7.128.1                           200 174 i
*> 198.137.240.32/27  38.7.128.1                           200 174 i 
*> 198.207.208.192/27 38.7.128.1                           200 174 iA
*> 204.4.196.32/27    38.7.128.1                           200 174 i
*> 204.4.196.64/27    38.7.128.1                           200 174 i
*> 204.4.196.96/27    38.7.128.1                           200 174 i
*> 204.68.218.0/27    38.7.128.1                           200 174 i
*> 204.180.67.160/27  38.7.128.1                           200 174 i
*> 206.181.125.188/30 38.7.128.1               0           200 174 i
*> 206.119.241.96/27  38.7.128.1                           200 174 i
*> 207.37.154.120/29  38.7.128.1                           200 174 i
*> 207.138.126.128/27 38.7.128.1                           200 174 i

Isn't it considered "bad" to be announcing nets that small, especially the
/30's?

--
Joseph W. Shaw - jshaw at insync.net    
Free UNIX advocate - "I hack, therefore I am."