The latest version if freenas as if a week ago, the windows box is up to date. After this happened (I took the freenas box home to do done testing and haven't tried duplicating it yet since I wanted to leave the box as is in case recovery was possible) I read up on the pitfalls of iscsi and zfs which is what I was testing.. I noticed performance was sluggish while writing so I believe this is a timeout. The data on this volume is not mission critical but I'd like to know why the volume reverts to a raw state, is it corrupted or is the problem on the windows side? To answer your question it only happened once after the iscsi volume was mounted and written to for about 3 hours during a backup operation