DNS Round Robin..

[Pete Ehlke]

On Fri, Feb 21, 2003 at 04:44:23PM -0800, Doug Barton wrote:
> On Fri, 21 Feb 2003, System wrote:
> 
> > I need to host one website on this two server so that even one server is
> > brought down for maintenance the other server can serve my clients. How
> > should I add A records in my DNS zone?
> 
> I think that your actual question was not addressed yesterday. If you put
> the A records for both real web servers in a hostname for your web site,
> both A records will always be returned by dns, regardless of whether the
> machine behind that IP is answering queries or not.
> 
> If what you actually want is failover or load balancing so that what dns
> points to is an IP address that is always pointing to something that is
> going to answer queries, you need a hardware solution like an alteon,
> foundry, etc. You could also hack together various solutions of your own
> to test if each box is up, and change dns if one goes down, but that's
> outside the scope of this list.
> 
Or something like lbnamed: http://www.stanford.edu/~riepel/lbnamed/

Before you do anything like attempting to laod-balance using the DNS,
though, you should probably carefully read the ISC page that's linked to
on the lbnamed page I referenced. It's not anywhere near as obvious as
most people seem to think it is.

-P.