Possibly odd question

[Cricket Liu]

> I had a client ask me today if he could have two separate nameservers
> for a domain, each pointing to a completely different IP address.  Let's
> say DNS A is 10.1.1.1 and DNS B is 172.16.1.1  DNS A resolves
> www.domain.com to 10.1.1.2 and DNS B resolves www.domain.com to
> 172.16.1.2  Besides the issues of synchronizing content between the two
> machines... is there a reason why this absolutely should not be done?
> His rationale is that if the connectivity for 10.1.1.0 goes down, then
> (after cached zone files from that server are purged) all future
> requests will fall back to the 172.16.1.1 serevr until the 10.1.1.0
> network is available again.  it sound sintriguing, but there's got to be
> a reason why nobody does this... :-)

I don't see anything wrong with this.  I've heard the same scheme
suggested before.  During normal operation (that is, when both
networks are reachable), I suppose it's possible that one web server
will get a majority of the load because the RTT of the corresponding
name server is lower than that of the other.  And, of course, you've
got to manage multiple copies of the zone. 

cricket

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