I use FreeBSD 8.3 and ezjail to administrate and maintain my jails. I know ezjail has backup and restore capabilities, but I thought I'd see if people have real world successes with moving jails between FreeBSD hosts. My main assumption is that in order to move a jail from one physical host to another the destination host must be on the same release of FreeBSD, both version and CPU architecture wise. The destination kernel must be built consistent to the source kernel to avoid issues too. Obviously networking will have to be handled during the relocation of the jail as well. Beyond that, I can't think of any other variables I need to be aware of. My second quandary is the feasibility to relocating a 8.3 jail to a 9.0 host. I'm thinking I could relocate the jail into ezjail's environment, then do an update on the jail using the 9.0 source, and a mergemaster with the jail against the 9.0 source, and it would emulate doing a full update from 8.3 to 9.0 without needing to rebuild the jail. Any other input or thoughts would be appreciated, if this all works it really makes jails even more awesome simply from a hardware upgrade perspective.