We have laptops that bounce around onto different wired and wireless networks on the LAN and sometimes connect remotely over VPN.
There are different IP ranges for wired, wireless and VPN connections and they are assigned by DHCP.
DNS records are not keeping up with the changes, so many laptops show up in DNS with incorrect IP addresses.
So, we frequently have to go into DNS and manually delete DNS records and then do a registerdns on the laptop and a flushdns on machine trying to reach the laptop. It is becoming labor intensive.
I thought DHCP was supposed to update DNS whenever it assigns a host a new IP address, but it doesn't seem to do this when there is already an existing entry for that host in DNS that was not yet cleaned up by scavenging. Seems to work for a new DNS entry only.
With Server 2008, how short can we make DHCP leases and scavenging intervals so that we can expect DNS records to be correct to within the last hour or less?