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