nanog mailing list archives

Re: Please help our simple bgp


From: Jared Mauch <jared () puck nether net>
Date: Tue, 31 Jan 2012 09:20:17 -0500


On Jan 30, 2012, at 9:27 PM, Ann Kwok wrote:

Hello

Our router is running simple bgp. "one BGP router, two upstreams (each 100M
from ISP A and ISP B)
We are getting full feeds tables from them

We discover the routes is going to ISP A only even the bandwidth 100M is
full

Can we set the weight to change to ISP B to use ISP B as preference routes?

Can the following configuration work?
What suggest to this weight no. too?

neighbor 1.2.3.4 description ISP B
neighbor 1.2.3.4 remote-as 111
neighbor 1.2.3.4 weight 2000

If this works, how is ISP B upstream connection is down?

Can it still be failover to ISP A automatically?

If it won't work, Do you have any suggestion?

Please implement an AS-PATH filter on your outbound to your
upstreams blocking yourself from re-annoucing their routes to them.

You can see many of these cases here:

http://puck.nether.net/bgp/leakinfo.cgi

eg:

41.217.236.0/24 852 3561 6453 15399 15399 15399 174 3491 33770 36997 37063 37113

15399 (Wananchi Online Limited) is leaking their upstream (Cogent) routes to TATA (6453)

- Jared

Current thread: