[79429] in North American Network Operators' Group
Re: BGP Anywhere - Global Redundancy
daemon@ATHENA.MIT.EDU (Kim Onnel)
Thu Apr 7 06:22:12 2005
Date: Thu, 7 Apr 2005 12:21:45 +0200
From: Kim Onnel <karim.adel@gmail.com>
Reply-To: Kim Onnel <karim.adel@gmail.com>
To: Vandy Hamidi <vandy.hamidi@markettools.com>
Cc: nanog@merit.edu
In-Reply-To: <8D40D9A9A9287340BBED080F91B310358977B3@mvmail05.markettools.com>
Errors-To: owner-nanog@merit.edu
There are New IOS features for such situations, take a look at
datacenter backup, SLB and these issues.
On Apr 7, 2005 2:35 AM, Vandy Hamidi <vandy.hamidi@markettools.com> wrote:
>
> All,
> We're an ASP and are considering adding a secondary Backup Datacenter
> (BDC) in the US to protect our web presence.
>
> My goal is to ensure automatic failover of my Primary DC's (IP) traffic
> to the BDC in the event of a catastrophic failure of the PDC.
>
> I'm considering geographic load balancing and BGP Anywhere as the two
> options. I'm clear on how the Geo LB works, but have some doubts about
> BGPAW as I've never implemented it before and documentation online is
> pretty weak to non-existent.
>
> Below is how I believe it should be done.
> From PDC:
> -Advertise CIDR block to all peers w/good metric (0 hop count)
> From BDC:
> -Advertise same CIDR block to all peers w/poor metric (+20 hop
> count)
>
> During normal operation, all ASes will route production traffic to PDC.
> In the event of catastrophic failure at PDC; PDC advertisements will
> cease, BDC route will become the only one on the net and traffic will
> route to the BDC.
>
> Questions:
> 1) Will this work?
> 2) Other suggestions or alternatives?
> 3) Any chance that traffic could flow to BDC for any reason?
> 4) Any internet etiquette I could be ignoring?
> 5) What would you estimate the failover time would be?
> 6) Assuming the routers at PDC and BDC pull down full routing table, how
> will the receipt of the PDC CIDR advertisement be treated? BGP rules
> say it will be dropped as a routing loop. What alternatives would I
> have if I want to be able to route that CIDR block traffic from the BDC
> to the PDC. Confed? Cisco conditional advertisements?
>
> Thanks all. This is the only place I can think of that would have the
> expertise to comment.
>
> -=Vandy=-
>
>
