Reverse DNS issues revoling around win 2003

[bigstack]

I am having issues with reverse dns...
my isp forwards the rdns requests to my dns servers.

when i perform a nslookup on one of my ip addresses that does not have a server currently running on it, yet has a ptr etc record on the dns server for that ip address it returns the correct domain name.

HOWEVER the moment i have a running server on that IP address reverse dns no longer works. it returns a servfail message.

has anyone ever had issues like this ?

the dns I am running is on a windows 2003 box/s.
most of the servers I run are linux.

this all sits behind a cisco router and firewall.

any thoughts / help would be appreciated.

[lammert]

Hi bigstack, Welcome to WebmasterWorld!

The SERVFAIL error is often internally generated by a DNS server if it can't communicate with an downstream DNS server. Maybe your main DNS servers are not configured as authorative servers but as caching servers, which try to send requests downstream as soon as they determine that a server is connected.