One Domain; Multiple IPs.

[Kevin Darcy]

Joseph S D Yao wrote:

> On Mon, Jul 16, 2001 at 07:12:33AM -0700, Dominik wrote:
> > We have one domain, which is mostly used to access a webserver.  The
> > webserver has two Internet connections; when one goes down, it can
> > still be accessed via the other.  Obviously, this server has two IPs
> > (one on each connection).  Unfortunately, www.domain on this box can
> > only resolve to one IP, as far as I know.  Is there any way to specify
> > two addresses, so that when one connection goes down, the nameserver
> > automatically starts responding with the IP for the other connection?
> >
> > I realize that there probably isn't any way to do this with standard
> > BIND.  One thing I was wondering about--how would NetSol react if we
> > submitted two nameservers for our domain, with each one responding to
> > the www.domain with a different IP?  Is this a solution in any way?
>
> You could have two name servers, giving out different IP addresses.
> That way, if one side goes down, only HALF the accesses would be to the
> dead IP address.

According to some interpretations, this is a DNS protocol violation. One
could rationalize it as a very volatile data, but even in that case the
protocol purists would insist that the SOA serial number be incremented
every time the zone "changed", i.e. every time a different response was
given by either nameserver.


- Kevin