Managing an Internet outage

[Rob Szarka]

At 03:31 PM 5/11/2008, you wrote:
>We occasionally have a situation where our Internet access is completely
>down. My Manager has asked about the viability of locating a DNS server
>off site, and during a situation when we're down, modifying it so that it
>resolves my entire domain to a single IP address. Web users would be
>redirected to that address, and a web page would explain we're off line.

Here's an alternate solution that might work for you: set up a proxy 
server located off-site at the same place (could be on the same host) 
as your new off-site DNS server. Configure the new DNS server to hand 
out the proxy's IP address as the A record for your web sites. Keep 
the TTL for the A records low.

During normal operation, some percentage of requests to your site 
would be served from the proxy, and they would be (roughly speaking) 
served to the visitors most likely to see a performance benefit. (Of 
course, if a large percentage of your traffic involves complex 
dynamic pages rather than static pages, graphics, etc., the gain 
might not be as large and/or more tuning might be required.) OTOH, 
when your connection goes down (ah, Cogent, gotta love 'em), everyone 
outside would wind up hitting the outside proxy, which could be 
configured to reply with a suitable message in this situation.