Following on for the issues I had with zfs receive crashing an Update 6 box, we just restarted the sending system to free up the stuck zfs processes and I received the following nasty surprise when I tried to clear system/filesystem/local:default which came up in maintenance after the restart: # svcadm clear system/filesystem/local:default # Mismatched versions: File system is version 3 on-disk format, which is incompatible with this software version 1!cannot mount ''tank/backup/ares/root'': Operation not supported svc:/system/filesystem/local:default: WARNING: /usr/sbin/zfs mount -a failed: exit status 1 Nov 14 17:54:01 svc.startd[7]: svc:/system/filesystem/local:default: Method "/lib/svc/method/fs-local" failed with exit status 95. Nov 14 17:54:01 svc.startd[7]: system/filesystem/local:default failed fatally: transitioned to maintenance (see ''svcs -xv'' for details) I was able to destroy the file system and continue. My question is, how did the version 3 file system get written? It was sent form the other box, but I would have expected the stream to be rejected. -- Ian.