[c-nsp] Conditional BGP

[Hank Nussbacher]

At 09:47 PM 18-10-08 +0500, Masood Ahmad Shah wrote:

I am curious if anyone else uses conditional BGP as a poor man's DRP?

Suppose you have site A with 192.168.1.0/24.  The site is connected to 2 
upstream ISPs and they have a number of servers at site A.  They now create 
a DRP site (site B), which is also connected to 2 upstream ISPs and they 
create a mirror copy of those servers from site A over at site B and assign 
them the *exact* same IP addresses as at site A.  They have the router at 
site B do conditional BGP, checking to see if it sees 192.168.1.0/24 from 
the Internet.  As soon as it disappears (site A is gone), site B starts 
announcing 192.168.1.0/24 to the Internet and all the DRP servers at site B 
are suddenly active.  Ignoring the syncing of the servers from site B to 
site A, what is the downside of such a "poor mans' DRP solution?

Regards,
Hank

>A nice book on BGP
>
>Practical BGP
>By Russ White
>
>Regards,
>Masood
>BLOG: http://www.weblogs.com.pk/jahil
>
>
>-----Original Message-----
>From: cisco-nsp-bounces at puck.nether.net
>[mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Mark Boolootian
>Sent: Wednesday, September 24, 2008 6:06 AM
>To: brandon at sterling.net
>Cc: cisco-nsp at puck.nether.net
>Subject: Re: [c-nsp] Conditional BGP
>
>
> >  2) View the NANOG presentation archives.  Several come to mind; I'll try
>to
> >  compile a list of suggestions, or just browse away.
>
>Search the presentation archive for Smith and BGP.  Philip Smith's
>BGP tutorials are outstanding.