We have 2 clustered Netware 6.5 sp7 servers running DNS and DHCP. The addresses are set to release every 4 days.

However when I'm in rconsole I get a ton of:
Recieved an unexpected Decline packet indentifying address X.X.X.X or the address failed a ping test.

If I go into the DNS/DHCP management console, sure enough there are tons of entries for computers that used to be here but aren't any more. So if I click on a specific address there are no associated NDS objects, no names, no resolution.

I've gotten rid of a couple manually by deleting them with (theoretically) no ill effect. Is there a way to set this up so that say any address that hasn't been pinged in a week goes away?

Could these bogus addresses be coming from our Microsoft Active Directory server?

Thanks in advance for your help