vxdump(1M)vxdump(1M)NAME
vxdump, rvxdump - incremental VxFS file system dump, local or across
network
SYNOPSIS
blocksize] records] density] filename] size] time] tracks] filesystem
blocksize] records] density] filename] size] time] filesystem
option [argument]... filesystem
option [argument]... filesystem
DESCRIPTION
copies to magnetic tape all files in the filesystem that have been
changed after a certain date. This information is derived from the
files and a timestamp file, by default copies the files to a tape drive
on a remote system. runs a process, on the remote machine to access
the tape device.
and support both and traditional command line invocations as shown
above. The original command line style is supported for compatibility
with previous versions of and for synonymy with the existing program
used for hfs file systems. For the traditional command line style,
option consists of characters from the set without any intervening
white space.
On most devices detects end-of-media and prompts you to change the
media if there is insufficient space, so it is not necessary to specify
the size of the device. However, if the dump will require multiple
tapes and the tapes are to be read using an older version of or if the
tape device handles end-of-media in a way that doesn't recognize, then
you must specify the size of the device using the option or a combina‐
tion of the options.
Options
If no arguments are given, the options are assumed to be and a default
file system is dumped to the default tape.
recognizes the following options:
number is a single digit in the range [0-9] and indicates the
dump level. All files modified since the last date
stored in the timestamp file for the same file system
at a lesser dump level will be dumped. Thus, the
option dumps the entire file system. If no date is
determined by the level, the beginning of (UNIX) time
is assumed.
The number of logical records per volume.
The logical record size is 1024 bytes. records can
also be specified with a suffix to indicate a unit of
measure other than 1024 bytes. You can append a or to
the number to indicate that the value is in kilobytes,
megabytes, or gigabytes, respectively. This option
overrides the calculation of tape size based on length
and density.
The blocking factor is taken from the
blocksize option argument. (default is 63 if is not
specified). Block size is defined as the logical
record size times the blocking factor. writes logical
records of 1024 bytes. Older versions of used a
blocking factor of 10 for tapes with densities less
than 6250 BPI, and 32 for tapes with densities of 6250
BPI or greater. dynamically determines the blocking
factor.
Cartridge.
Specifies using a cartridge instead of the standard
half-inch reel. This sets the density to 1000 BPI and
the blocking factor to 63. The length is set to 425
feet. -c is incompatible with the -d option, unless
you specify a density of 1000 BPI with that option.
The density of the tape (expressed in BPI)
used to calculate the amount of tape used per tape
reel. If is specified, a default density value of
1600 is assumed for a reel tape.
Place the dump on the file
filename instead of the tape. If the name of the file
is writes to the standard output. This option can be
of the form to specify a tape device on a remote
machine.
Whenever requires operator attention, notify all users in group
by means similar to that described by wall(1M).
Use rather than for timestamp information.
size is the size of the dump tape, specified in feet. When
the specified size is reached, waits for reels to be
changed. If is specified, a default size value of
2300 is assumed for a reel tape.
-t tracks Specifies the number of tracks for a cartridge tape.
The default is nine tracks. -t is not compatible with
the -d option.
Use the specified date as the starting time for the dump
instead of the time determined from looking in the
timestamp file. The format of date is the same as
that of This option is useful for automated dump
scripts that wish to dump over a specific period of
time.
· You can specify only for incremental dumps; using
for a level 0 dump returns an error.
· is mutually exclusive with the option.
· If you enter an improperly formatted date, returns
an error message and terminates the dump.
If the dump completes successfully,
write in the timestamp file the date when the dump
started. This file records a separate date for each
file system and each dump level. The format of the
timestamp file is user-readable and consists of one
free-format record per line: file system name, incre‐
ment level and dump date in format. The timestamp
file can be edited to change any of the fields if nec‐
essary. The option is ignored for partial dumps.
For each file system in the timestamp file
print the most recent dump date and level, indicating
which file systems should be dumped. If is specified,
all other options are ignored and exits immediately.
Operate like
but print only file systems that need to be dumped.
Operands
recognizes the following operand:
filename Name of the file that contains a list of all files in
the to be copied to magnetic tape.
Operator Interaction
requires operator intervention for any of the following conditions:
· end of tape
· end of dump
· tape-write error
· tape-open error
· disk-read error (if errors exceed threshold of 32).
In addition to alerting all operators implied by the option, interacts
with the control terminal operator by posing questions requiring or
answers when it can no longer proceed or if there is a serious problem.
Because making a full dump typically requires considerable time, estab‐
lishes a checkpoint at the start of each tape volume. If, for any rea‐
son, writing that volume fails, with operator permission, restarts from
the checkpoint after the old tape is rewound and removed and a new tape
is mounted.
periodically reports information to the operator, including estimates
(typically low) of the number of blocks to write, the number of tapes
it requires, time required to complete, and the time remaining until
tape change. The output is verbose to inform other users that the ter‐
minal controlling is busy and will be for some time.
Compatibility
The dump tape format is independent of the VxFS disk layout. A dump of
a file system with the Version 4 disk layout can be restored on a file
system using the Version 2 disk layout or even a file system of another
file system type, with the following exceptions:
· Files larger than 2 GB cannot be restored by earlier versions of If
a file larger than 2 GB is encountered, an older skips the file and
returns this message:
· Files larger than 2 GB cannot be restored on a file system that does
not support large files (see mount_vxfs(1M)).
· A file with a large uid (user ID of the file owner) or large gid
(group ID of the file owner) cannot be restored correctly on a file
system that does not support large IDs. Instead, the owner and/or
group of the file will be that of the user invoking (A large ID is a
value greater than 65535. The VxFS Version 2 disk layout does not
support large IDs).
· Files with VxFS extent attributes (see setext(1M)) cannot be
restored on a file system of a type that does not support extent
attributes.
If you use to produce a dump intended for an earlier version of and if
the dump requires multiple tapes, you should use the or option.
Dumps produced by older versions of can be read by the current version
of
Notes
Perform dumps with the file system unmounted or the system in single-
user environment (see init(1M)) to ensure a consistent dump. If you
have the HP OnLineJFS product installed, the dump can be performed in
the multi-user environment using a snapshot file system with the online
backup facility (see the option of mount_vxfs(1M)).
Up to 32 read errors on the file system are ignored.
Each reel requires a new process; parent processes for reels already
written remain until the entire tape is written.
does not dump information about ACLs, therefore does not restore infor‐
mation about ACLs.
Neither nor work with Storage Checkpoints.
A version of resides in for use when the system is in single user
state.
EXAMPLES
In the following example, assume that the file system is normally
attached to the file tree at the root directory,
In this example, the entire file system is dumped on and the size of
the tape is 2 gigabytes.
Using the traditional command line syntax and specifying the tape size
in logical records:
The option argument goes with the option letter as it is the first
option letter that requires an option argument. The option argument
goes with the option letter as it is the second option letter that
requires an option argument.
AUTHOR
and are based on the and programs from the 4.4 Berkeley Software Dis‐
tribution, developed by the the University of California, Berkeley, and
its contributors.
FILES
Default legacy DSF tape unit to dump to.
Default persistent DSF tape unit to dump to.
New format-dump-date record. This is the default file for VxFS.
New format-dump-date record. Can be substituted for by using the /CR
-o option.
Dump table: file systems and frequency.
Mounted file system table.
Used to find group
SEE ALSOdump(1M), init(1M), mount(1M), mount_vxfs(1M), rmt(1M), setext(1M),
vxrestore(1M), wall(1M), close(2), open(2), ctime(3C), getopt(3C),
fstab(4), mnttab(4).
vxdump(1M)