One side effect of rebuilding the server that runs pretty much everything on my home network was that I had to migrate the DHCP database (twice – first to a virtual machine operating as a temporary server, and then back to the original hardware after it had been rebuilt).

I knew that it was possible (I did it from NT 4.0 to Windows 2000 for a client few years back) but hadn’t done it recently.

It turned out to be pretty straightforward – all of the details are in Microsoft knowledge base article 325473 but basically on the source (Windows 2000 Server) server, stop the DHCP service and use jetpack.exe to tidy up the database, then use the DHCP database export/import resource kit tool (dhcpexim.exe) to dump the database and finally import it on the target (Windows Server 2003) server using the network shell (netsh.exe). The second migration was even quicker – for a Windows Server 2003 source and target it just involves a couple of netsh commands. Finally, don’t forget to disable redundant DHCP services (or deauthorise the servers in Active Directory) to prevent multiple DHCP servers from servicing clients simultaneously.