I found myself doing yet another Windows 2003 IAS Radius server migration to 2008 R2 NPS. I found that I had my prior notes and was able to do this quickly but, hell, if I’m looking this up in my own notes I may as well just post this succinct little procedure.
Copy %windir%\syswow64\iasmigreader.exe (this may also be on the installation media at \sources\dlmanifests\microsoft-windows-iasserver-migplugin) from the 2008 server to the 2003 server and run. It will spit out where the backup file was created. Copy this over
C:\>IasMigReader.exe Start to convert IAS configuration. IAS configuration is successfully saved to "C:\WINDOWS\system32\IAS\ias.txt".
Copy the ias.txt file that is generated back to the 2008 R2 server and import the configuration like so:
At the 2008 R2 Server:
netsh nps import filename="path\ias.txt"
Don’t forget to register your NPS service in AD or configuration settings be damned, NPS will just will not work.