I took one of my FreeNAS servers from 8.3 up to 9.1 last night using the GUI update. It was as easy as it gets. All you have to do is d/l the binary to your local machine and copy the checksum for that binary to the clipboard. From the FreeNAS web interface navigate to the binary location and paste the checksum into the input box on the screen and click apply The server updates and reboots in about 3 minutes. After all of that I'm probably going to roll the server back to 7.2 however. The jump from 7.x to 8.x involved a major re-write of the server ( I think it also is being run by someone other than the original developer) which added some cool stuff but also takes away features plus makes the distro a resource pig. The new version ships with ZFS support but requires more CPU and RAM resources than my server can supply. It's only an ATOM 1.6 Ghz processor with 2GB RAM. A full blown ZFS installation calls for 8GB RAM to be efficient. Also in 8.x they took away some of the cool extras such s media servers and other add ons. The current 9.1 distro has many of the features available again but they require ZFS to run. Maybe if I build a new NAS I'll plan for the latest but for now, the 7.2 OS runs just fine and is more than adequate.