Please help our simple bgp

Matthew Reath matt at
Sat Feb 4 07:55:20 UTC 2012

> 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 description ISP B
>  neighbor remote-as 111
>  neighbor 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?
> Thank you for your help


I've done this for a few customers that have requested it. Some engineers
complain that advertising /24 routes dilutes the Internet routing tables,
which is true in some regards.  However, this does work in many situations
to "balance" things out.

Check out my blog post that walks through this procedure:


Matt Reath
CCIE #27316 (SP)
matt at |

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