I've been using fssconfig to create snapshots of my filesystems and then
dumping them to tape.

But I just noticed the -x and -X options on the dump(8) man page...

 -x snap-backup
         Use a snapshot with snap-backup as backup for this dump.  See
         fss(4) for more details.  Snapshot support is experimental.  Be
         sure you have a backup before you use it.

 -X      Similar to -x but uses a file system internal snapshot on the
         file system to be dumped.



3 things:

(1) What has to be done to make fss no longer experimental? I have and
only good results (except when creating snapshots of LFS filesystems).

(2) What's a `file system internal snapshot'?

(3) Is there any more information on the -x option? I'd like to know the
parameters it uses for fssconfig.


It would be nice if the real filesystem would end up in /etc/dumpdates.
That's the level of detail I'm looking for.

I'd be happy to test and contribute to documentation based on what I find...

Louis