RE: Facility wide DR/Continuity

["Ricky Duman" <rduman () internap com>]

Drew,

IMO as your %Availability goes up, (99, 99.9, 99.99.....100%)... your
price to implement will go up exponentially.  That being said, a
majority of this will depend on what your budget is to achieve your
desired availability.

You can either

- Failover to backup servers using DNS (but may not be instant)
                Also should consider replication solution if your
resources need fresh data

On the high-end you can:
        - run secondary mirror location...replicating data 
        - Setup BGP announcing your IP block out of both locations
        - You should have a private link interconnecting your sites for
your IBGP session.




-----Original Message-----
From: Drew Weaver [mailto:drew.weaver () thenap com] 
Sent: Wednesday, June 03, 2009 8:10 AM
To: 'nanog () nanog org'
Subject: Facility wide DR/Continuity

Hi All,

I'm attempting to devise a method which will provide continuous
operation of certain resources in the event of a disaster at a single
facility.

The types of resources that need to be available in the event of a
disaster are ecommerce applications and other business critical
resources.

Some of the questions I keep running into are:

                Should the additional sites be connected to the primary
site (and/or the Internet directly)?
                What is the best way to handle the routing? Obviously
two devices cannot occupy the same IP address at the same time, so how
do you provide that instant 'cut-over'? I could see using application
balancers to do this but then what if the application balancers fail,
etc?

Any advice from folks on list or off who have done similar work is
greatly appreciated.

Thanks,
-Drew