Reverse DNS for host with multiple IPs
Posted on 2009-04-15
Correct me if I'm wrong, but I thought setting up reverse DNS for hosts with multiple IPs is pretty straightforward?
We have one customer that has 2 ADSL lines with 2 different suppliers and an internal mail server. There are two A records setup for their mail server hostname pointing to the two different IPs. Each supplier has setup reverse DNS entries for each IP resolving to the same hostname. This has all worked fine for over a year.
Now one of the lines has been switched to a different supplier and their hostmaster is telling me it's not possible to setup rDNS for a host that has two forward lookup IPs??
"A single A record has to point to a single IP address, you cannot have mail.yourdomain.com pointing at 2 different IP addresses it just will not work."
That is true - a single A record has to point to a single IP. But there's no reason why there can't be two A records for the same hostname right?
Or am I going senile?