Another HAMMER crash

[Matthew Dillon]

:Yes, that helped.
:
:>     I recommend always doing a normal mount and using cd @@0x<TID> to
:>     push into a snapshot.
:
:I had no snapshot. I just wanted to try the as-of mount. I read the
:manual but failed to understand it. hammer(5) says:
:
:'Prior versions of files or directories are accessible by appending @@
:and a transaction ID to the name.'
:
:I could not access them this way.
:
:-- 
:Gergo Szakal MD <bastyaelvtars at gmail.com>
:University Of Szeged, HU

    You can generate the transaction ids manually using 'hammer synctid',
    or you can extract them from a file using 'undo -i <filename>'.  You
    get a snapshot every 30-60 seconds even if you don't lift a finger,
    but unless you record the transaction ids somewhere you'd have to
    do some sleuthing (e.g. with undo -i) to get them.

    Typically what you would do is have a cron job create a convenient
    snapshot softlink once an hour, once a day, whatever, like this:

    mkdir /mnt/snapshots
    hammer snapshot /mnt/snapshots
    (creates a softlink in that directory called snap-DATE-TIME which
    gives you a snapshot of the entire filesystem as-of that point).

    If you have a snapshots directory you can then prune the filesystem
    based on the contents of the directory.  Hmm.  I guess we need more
    of a tutorial on how to get started with snapshots in our hammer(5)
    man page.

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>