nisc-03292 (ticket update) badly flapping prefix (204.4.27/24)

PSI NISC nisc at
Mon Sep 11 21:55:43 UTC 1995

Ticket #nisc-03292 	09/11/95-17:55:14 libby 	SUBJECT: badly flapping prefix (204.4.27/24)
Posted by: Cole G. Libby


Allow me to correct the too quick response you
received from one of my people this weekend.

We agree that this network is flapping far too 
many times and that this is a bad thing. Clearly
the customer cannot be getting much useful service
here either.

We are contacting the customer to assist with his
configuration and reduce the number of route flaps.
This is something that we do periodically with all
our dialup customers to ensure that they are getting
good service and are being good 1 neighbors.
This is not the only network in this circumstance that
we are addressing.

This network is not in a PSI CIDR block and is therefore
portable and not a candidate for aggregation. 

Additionally, this network is used with a legacy account 
that was purchased at a time when this was permitted.
In January, we have stopped allowing new dialup customers to 
use networks that are not in PSINet CIDR blocks. Since these
blocks are indeed aggregated this has the effect you desire.


Cole Libby
Manager, PSI Customer Support

 >	The customer that this network belongs to is a dial-up customer, and
 >as such, when his connection is up, we broadcast his network IP, and stop
 >broadcasting when he disables his connection. We are unable to prevent his 
 >route from propagating in the face of what could be frequent log-in/log-outs.
 >Aaron Silver
 >PSI Customer Support 
 >Ticket #nisc-03292 	09/10/95-17:50:04 silvera 	SUBJECT: badly flapping prefix (204.4.27/24)
 >Posted by: Sean Doran <smd at>
 >Hi -
 >  Could you please look into this badly flapping prefix with
 >a view to stopping it from oscillating this wildly?
 >  Thanks!
 >	Sean.
 >- --
 >SL-CHI-12> sh ip bgp
 >BGP routing table entry for, version 656911
 >Paths: (2 available, no best path)
 >  1239 174 (history entry)
 > (metric 15) from (
 >      Origin IGP, metric 1, localpref 90, external
 >      Dampinfo: penalty 2867, flapped 171 times in 20:14:19
 >  1239 174 (history entry)
 > (metric 15) from (
 >      Origin IGP, metric 1, localpref 90, external
 >      Dampinfo: penalty 2862, flapped 170 times in 20:13:55

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