HP-UX Reference (11i v2 07/12) - 1M System Administration Commands N-Z (vol 4)

v
vxdump(1M) vxdump(1M)
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
vxrestore. If a file larger than 2 GB
is encountered, an older
vxrestore skips the file and returns this message:
Resync restore, skipped num blocks
• 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
vxrestore. (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
vxdump to produce a dump intended for an earlier version of vxrestore, and if the dump
requires multiple tapes, you should use the
-s, -d,or-B option.
Dumps produced by older versions of vxdump can be read by the current version of vxrestore .
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
snapof=file 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.
vxdump does not dump information about ACLs, therefore vxrestore does not restore information
about ACLs.
Neither vxdump nor vxrestore work with Storage Checkpoints.
A version of vxdump resides in /sbin for use when the system is in single user state.
EXAMPLES
In the following example, assume that the file system /mnt is normally attached to the file tree at the root
directory, (/).
In this example, the entire file system (/mnt) is dumped on /dev/rmt/0m and the size of the tape is 2
gigabytes.
vxdump -0 -B 2g -f /dev/rmt/0m /mnt
Using the traditional command line syntax and specifying the tape size in logical records:
vxdump 0Bf 2097152 /dev/rmt/0m /mnt
The option argument 2097152 goes with the option letter B as it is the first option letter that requires
an option argument. The option argument /dev/rmt/0m goes with the option letter f as it is the
second option letter that requires an option argument.
AUTHOR
vxdump and rvxdump are based on the dump and rdump programs from the 4.4 Berkeley Software
Distribution, developed by the the University of California, Berkeley, and its contributors.
FILES
/dev/rmt/0m Default tape unit to dump to.
/etc/dumpdates New format-dump-date record. This is the default file for VxFS.
/etc/vxdumpdates New format-dump-date record. Can be substituted for /etc/dumpdate
by using the /CR -o option.
652 Hewlett-Packard Company − 3 − HP-UX 11i Version 2: December 2007 Update