BACKUP(8) BACKUP(8)
NAME
backup, tobackup, dumparenas, restore - backup venti arenas
to blu-ray discs or restore from them
SYNOPSIS
backup [ -np ] [ -d dev ] [ -s set ]
tobackup [ set ]
dumparenas dev arena ...
restore arena-# [ dev ]
DESCRIPTION
These programs reside in /sys/lib/backup and provide a means
to backup venti(8) storage to Blu-ray (or other large opti-
cal) discs, while keeping track of which arenas have been
written to which discs. Multiple backup sets are supported,
as is (re)loading a venti store from a backup thus made.
The first time that backup is run, it will dump all sealed
venti arenas. Thereafter, it will append only those sealed
arenas not already written to a disc within the given backup
set. The -s option uses a backup set other than the
default. The -d option uses a disc burner other than the
default `/dev/sdD0'. The -n option goes through the motions
but does not burn any tracks on the Blu-ray disc. As a
side-effect, backup run on the default dump set, `set1',
will also print the last few fossil dump scores unless the
-p option is given.
Tobackup prints the names of all the sealed arenas not yet
backed up to a disc in the current set.
Dumparenas copies the named arenas, one per track, to the
device dev, which is first mounted via cdfs(4).
Venti/rdarena is used to extract each arena.
Tobackup and dumparenas are invoked internally by backup.
Restore copies each data track (assumed to be a saved arena)
on dev (by default, `/dev/sdC0') into its appropriate place
in the venti arenas partition (locally, /dev/sde0/arenas),
thus adding the arena to the current venti store. The arena
size of the arena partition must match the size of the are-
nas on optical disc (except for ~60K of trailing debris on
the optical disc arenas).
Arena-# must be the number (starting from zero) of the first
arena slot in the arenas partition that you wish to restore
into from the current optical disc (not necessarily that of
the first arena on the disc). Restore will prompt for con-
firmation that the first arena is the correct one, after
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BACKUP(8) BACKUP(8)
printing a summary of its arena header. Typing `y' will
proceed normally, `n' will abort all processing, and `skip'
will cause restore to proceed to the next track and ask for
confirmation of it.
The arenas partition must be formatted (see fmtarenas in
venti-fmt(8)) before restoring into it. When all the arenas
have been restored, it will be necessary to build a new
venti index, the usual steps being to run checkarenas,
fmtisect, fmtbloom, fmtindex, and buildindex -b, all from
venti-fmt(8).
FILES
/sys/lib/backup backup scripts and records
set1 subdirectory containing records for default
backup set
/sys/log source of dump scores
SOURCE
/sys/lib/backup
SEE ALSO
venti(1), cdfs(4), venti(8), venti-fmt(8), venti-backup(8)
Venti Backup on Blu-Ray Discs
BUGS
Assumes a single arenas partition named `arena0'. Assumes
that the file server's arenas are accessible on it as
`/dev/fs/arena0'.
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