Thanks Arran. Honestly, I don't have any idea about CoA and DM but I know that I can use SNMP on the server which runs Debian 6.0. This might be out of the RADIUS scope but I need a little bit more information on this to work it out. How should I send the PoD to SNMP? Will SNMP handle such request by default or I have to set it up for this?
Forget about using DM if its not supported by the daemon.
I'm saying write a simple script on the RADIUS server that does an SNMP set on the required OIDs registered by your VPN daemon on your remote machine.
Or just write a simple daemon in perl to call the command line utility on the remote server.
Even a useful URL would be a great help cause I couldn't find anything by googling the keywords came to my mind.
Here's an example of translating SNMP requests into status requests for FreeRADIUS.