I've changed a couple servers from DHCP to use static IPs, but for some reason the domain controller that is acting as DNS server still resolves to the old IP. What could be causing this? Unfortunately I don't have access to the domain controller (belongs to corporate IT) but I'm still curious how you would troubleshoot this issue.
Static IP addresses are not automatically registered with DNS controllers the way that DHCP granted ones are. I am sure that there is a way to force the registration although I don't know what it is. Alternatively, if you own the DHCP server you could do the static assignments with DHCP reservations instead of static assignments on the server which would cause them to register the IPs with the DNS server when they obtain the lease. Hope that helps.