AMVERIFY(8) System Manager's Manual AMVERIFY(8)NAME
amverify - check an Amanda tape for errors
SYNOPSIS
amverify config [ slot [ runtapes ] ]
DESCRIPTION
Amverify reads an Amanda format tape and makes sure each backup image can be processed by amrestore and, if possible, the appropriate
restore program (e.g. tar).
Amverify runs amrestore on each file of the tape and pipes the output to a restore program (if available) with an option to create a cata-
logue of the backup. The catalogue itself is discarded. Only the success or failure of the operation itself is reported.
If the backup image cannot be processed by the restore program, e.g. if it was written on a different operating system, the image is sent
through dd to /dev/null. This still determines if the tape is readable, but does not do any internal consistency check on the image.
If config is set up to use a tape changer, the slot argument may be used to choose the first tape to process. Otherwise, the current slot
is used.
The runtapes configuration parameter determines how many tapes are processed unless it is specified on the command line.
See the amanda(8) man page for more details about Amanda.
AUTHOR
Axel Zinser <fifi@icem.de>
SEE ALSO amrestore(8), amanda(8), amverifyrun(8)AMVERIFY(8)
Check Out this Related Man Page
AMRESTORE(8) System Manager's Manual AMRESTORE(8)NAME
amrestore - extract backup images from an Amanda tape
SYNOPSIS
amrestore [ -r | -c | -C ] [ -b blocksize ] [ -p ] [ -h ] tapedevice | holdingfile [ hostname [ diskname [ datestamp [ hostname [ diskname
[ datestamp ... ]]]]]]
DESCRIPTION
Amrestore extracts backup images from the tape mounted on tapedevice or from the holding disk file holdingfile that match hostname,
diskname and datestamp patterns given on the command line. The tape or holding file must be in a format written by the amdump or amflush
program.
If diskname is not specified, all backups on the tape for the previous hostname are candidates. If datestamp is not specified, all backups
on the tape for the previous hostname and diskname are candidates. If no hostname, diskname or datestamp are specified, every backup on
the tape is a candidate.
Hostname and diskname are special expression descibe in the "HOST & DISK EXPRESSION" section of amanda(8). Datestamp are special expres-
sion describe in the "DATESTAMP EXPRESSION" section of amanda(8). For example, if diskname is "rz[23]a", it would match disks rz2a and
rz3a.
Datestamp is useful if amflush writes multiple backup runs to a single tape.
Unless -p is used, candidate backup images are extracted to files in the current directory named:
hostname.diskname.datestamp.dumplevel
OPTIONS -b Set the blocksize used to read the tape or holding file. All holding files must be read with a blocksize of 32 KBytes. Amrestore
should normally be able to determine the blocksize for tapes on its own and not need this parameter.
The default is 32 KBytes.
-p Pipe output. The first matching backup image is sent to standard output, which is normally a pipe to restore or tar, then amrestore
quits. It may be run again to continue selecting backups to process. Make sure you specify the no-rewind tapedevice when doing
this.
Note: restore may report "short read" errors when reading from a pipe. Most versions of restore support a blocking factor option to
let you set the read block size, and you should set it to 2. See the example below.
-c Compress output using the fastest method the compression program provides. Amrestore normally writes output files in a format
understood by restore or tar, even if the backups on the tape are compressed. With the -c or -C option, amrestore writes all files
in compressed format, even if the backups on the tape are not compressed. Output file names will have a .Z or .gz extension depend-
ing on whether compress or gzip is the preferred compression program. This option is useful when the current directory disk is
small.
-C Compress output using the best method the compression program provides (may be very CPU intensive). See the notes above about the
-c option.
-r Raw output. Backup images are output exactly as they are on the tape, including the amdump headers. Output file names will have a
.RAW extension. This option is only useful for debugging and other strange circumstances.
-h Header output. The tape header block is output at the beginning of each file. This is like -r except -c or -C may also be used to
compress the result. Amrecover uses the header to determine the restore program to use.
If a header is written (-r or -h), only 32 KBytes are output regardless of the tape blocksize. This makes the resulting image usable as a
holding file.
EXAMPLES
The following does an interactive restore of disk rz3g from host seine, to restore particular files. Note the use of the b option to
restore, which causes it to read in units of two 512-byte blocks (1 Kbyte) at a time. This helps keep it from complaining about short
reads.
% amrestore -p /dev/nrmt9 seine rz3g | restore -ivbf 2 -
The next example extracts all backup images for host seine. This is the usual way to extract all data for a host after a disk crash.
% amrestore /dev/nrmt9 seine
If the backup datestamp in the above example is 19910125 and seine has level 0 backups of disks rz1a and rz1g on the tape, these files will
be created in the current directory:
seine.rz1a.19910125.0
seine.rz1g.19910125.0
You may also use amrestore to extract a backup image from a holding disk file that has not yet been flushed to tape:
% amrestore -p /amanda/20001119/seine.rz1a.2 | restore -ivbf 2 -
Amrestore may be used to generate a listing of images on a tape:
% mt -f /dev/nrmt9 rewind
% amrestore -p /dev/nrmt9 no-such-host > /dev/null
This asks amrestore to find images for host no-such-host. It will not find any entries that match, but along the way will report each
image it skips.
CAVEATS
GNU tar must be used to restore files from backup images created with the GNUTAR dumptype. Vendor tar programs sometimes fail to read GNU
tar images.
AUTHOR
James da Silva <jds@cs.umd.edu>
University of Maryland, College Park
SEE ALSO amanda(8), amdump(8), amflush(8), tar(1)restore(8)AMRESTORE(8)