Configuring multi-home failover

Stephane Bortzmeyer bortzmeyer at
Fri Jan 18 20:25:24 UTC 2002

On Friday 18 January 2002, at 11 h 46, 
"Mike Stubbers" <mikest at> wrote:

> I am wanting to configure a secondary ISP to be used as fail over only for
> our primary.

Most people who have two links use them also for load-sharing. A link to an 
ISP is expensive enough so you don't want to keep it unused "just in case".

Is it because the second ISP charges a lot according to the volume actually 

>  At this point both ISP's come into the same 7500 router 

So much for the redundancy. 

> have an established BGP session with our primary provider.

Do you have a private AS number or already a public one?

> Can those of you doing this already tell me the optimum way to set this up?
> Is this best done on my end or by having my secondary discover our
> disappearance and begin announcing?

I would say that it is better done on your end because it will allow you to change your policy (see above my remarks). Also, it is "the normal way" of operation for BGP.

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