2 name servers one ip

[Kevin Darcy]

Paul A wrote:
> I recently took over a name server that I want to join with my current name
> server.
> I was thinking of having two A RRs, for the current name server and the
> server I just took over, pointing to the same ip.
> Example:
>
> Ns1.currentns.com would point to 1.1.1.1 and so would ns1.newns.com.
>
> I want to do this so that all customers currently pointing their zones to
> ns1.newns.com don't have to make modifications with the NICs.
>
> I know this is obviously possible but is this against the RFC's and is it
> recommended or not ?
>   
I don't think this is against the RFCs. You are required to have at 
least 2 actual nameservers for any given zone, but I don't think there's 
any restriction on 1, both or all of those nameservers being referred to 
by multiple names. If there were such a restriction, then all of those 
folks who subscribe to the cult belief that NS records should always be 
"in-zone" (i.e. should always point to a name that's inside the zone for 
which the NS record exists), would be violating that restriction left 
and right.

The main problem, I think, with having multiple names resolve to the 
same IP address, is how to provide matching forward and reverse records. 
Adding a reverse record for every name that points to a particular 
address is not scalable of course, but how does one prioritize among 
those names, to decide which one gets a matching PTR record?

                                                                         
                                       - Kevin