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When
restoring files backed up with the backup, cpio, or tar commands,
find out FIRST whether RELATIVE or ABSOLUTE
pathnames were used BEFORE the restore is initiated.
We recommend using RELATIVE.
- Relative
pathnames will have a ./
pre-fixed to their path. These files will be restored
relative to the current directory.
- Absolute
pathnames won't have the ., just the /.
These are restored with the full pathname to the exact directory
as specified on the archive device.
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Command
typically used to backup files on an AIX platform. Distribution
tapes for AIX are in this format. This
command will span across multiple tapes.
Backup
by INODE is not recommended because it eliminates the capability
to selectively restore files by filename.
If
you have more data to backup than can fit on one tape, you will
probably want to perform INCREMENTAL backups for files that have
been modified within the last 24 hours for each day of the work
week, followed by making a complete backup of the system on the
weekend.
The
error message Volume on /dev/rfd0 is not
in backup format is generated when an attempt is made to
extract a file NOT created by the backup command:
If
your backup was successful, the last item logged by 'backup' is
the time the backup finished and the number of 512 byte block
that were archived.
Example
message of a successful backup:
Backup finished on Sat Aug 1 15:22:34 CDT 1992; there are 8700 blocks on 1 volumes.
| Options |
What
it does |
| -i |
Read
standard input |
| -v |
List
names of files being backed up |
| -f |
Name
of output device (typically de/v/rmt0 for tape drive) |
| -e |
Won't
attempt to compress or pack files that are greater than 24
MB. |
| -q |
Won't
prompt user to insert tape |
| -p |
Pack
data. Backup images by default are NOT packed. If you
wish to pack your data, use this option. The restore command
has enough intelligence to determine if a backup image is
packed or not and take appropriate action |
| Examples |
What
it does |
| find
/u -print | backup -ivf/dev/rmt0 |
Backup
the file system /u to tape device using ABSOLUTE
pathnames. |
| find
. -print | backup -iepqvf/dev/rmt0 | tee /tmp/BACKUP.LOG |
Backup
files and directories under current directory (.) using RELATIVE
pathnames. The tee (|) will take as input the output of the
backup command (filenames being copied) and write them to
the log file 'BACKUP.LOG' for later review. |
| find
/faxdata -mtime -1 -type f -print | backup -ivf/dev/rmt0.1 |
Find
any REGULAR files (-type f) that have been modified within
the past 24 hours (-mtime -1) and write them to the tape device
but don't rewind (/dev/rmt*.1) the tape after
backup has finished. |
| backup
-ivqf/dev/fd0 |
Backup
files interactively. Select the file(s) to backup by typing
in the file's name. When done, press ^D
to finish. |
| find
/ -print|backup -icvqf/dev/rmt0-1 |
If there
is more than one tape drive attached to the system, then you
can specify a range of devices to the -f flag of the backup
command. (/dev/rmt0-1) |
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Utilities
to compress or expand data. The compress command reduces
the size of the named file(s) and renames it with a .Z extension.
Compressed files can be restored to their original form using
the uncompress command. This utility
appears to have a more EFFICENT packing scheme than the PACK/UNPACK
commands.
| Examples |
What
it does |
| compress
-v /tmp/junk |
File
/tmp/junk is compressed and gets renamed to /tmp/junk.Z. -v
displays the percentage of file shrinkage |
| uncompress
/tmp/junk.Z |
Restores
file to original file type and file size and changes the name
to /tmp/junk. |
1)
find . -print | backup -ivqpf /tmp/roger.bck
2) compress /tmp/roger.bck
3) find /tmp/roger.bck.Z -print | backup
-ivqf/dev/fd0 |
The 3
commands will backup the current directory and compress that
backup image to a floppy diskette. |
1)
restore -xvf/dev/fd0
2) uncompress < /tmp/roger.Z | restore
-xvf- |
Restore
the files archived from a floppy diskette. (In this example
assume restored file=roger.Z) Uncompress the compressed
image and restore this file back to the file system |
| zcat
/tmp/junk.Z > /tmp/junk1 |
Uncompresses
/tmp/junk.Z into /tmp/junk1 |
| find
/u/COMPANY -print | xargs pack -f |
Packs
all the files under the specified directory (/u/COMPANY) |
| find
/u/COMPANY -print | xargs unpack |
Unpacks
all the files under the specified directory (u/COMPANY) |
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Copies
files to/from an archive storage device. This command is often
used to copy files from UNIX to AIX systems. This command will
span across multiple tapes. cpio stands for CoPy Input
to Output.
| Options |
What
it does |
| -c |
Writes
header information in ascii format for portability across
UNIX systems. The
message Out of phase--get help is
generated when an attempt is made to extract a file not in
cpio format OR if the archive tape was written with the -c
option. The
cpio command doesn't have this option specified when attemping
to extract files from the media (eg., cpio -icdumpv
< /dev/rmt0) |
| -r |
When
restoring will prompt for new path/file to restore to |
| -v |
List
the file name as it's being copied |
| -i |
Read
from standard input, i.e. keyboard |
| -u |
Copies
unconditionally. Older file replaces a newer one. Files with
older modification times will replace files with newer modification
times. |
| -d |
Creates
directories, if applicable |
| -t |
For
table of contents |
| -C1 |
Performs
block I/O in 512 byte blocks, if
the block size of the device that wrote the data on the tape
was set to 512 bytes. Make sure you
read with the same block size. If the block size that the
data was written to and about to be read from are two different
sizes, this message will be displayed: Cannot
read from the specified device |
| Examples |
What
it does |
1)
cd /u/roger
2) find . -print | cpio -ocv > /dev/fd0 |
Reads
file names using the find command and copies to the floppy
drive (/dev/fd0). |
| find
. -cpio /dev/fd0 -print |
Saves
files in current directory and writes this info to floppy.
Same command as above except much faster. |
1)
cd /u/roger
2) cpio -icuvd < /dev/fd0 |
Restore
files and directories saved on the floppy device. These files
are restored under the current directory (/u/roger) Only
if relative pathnames (./<filename>)
were used. |
| cpio
-itvcC1 < /dev/rmt0 |
List
the table of contents from a tape device. |
1)
cd /u/roger
2) find . -print | cpio -dumpv /u/jerry |
Copies
all files FROM one directory TO another WITHOUT changing the
permissions, owner/group or modification date of the file.
Use the following command to verify that all files were copied: |
| find
/u/roger -print | wcfind /u/jerry -print | wc |
If the
number of files encountered is the same for both directories
its safe to assume that the directories are identical. NOTE:
that the number of blocks allocated to the SOURCE directory
(/u/roger) may be larger than the DESTINATION directory (/u/jerry),
since compaction of the directory structure will have occurred
at the destination end. |
| cpio
-imv /home/roger/.profile < /dev/fd0 |
Selectively
restore the /home/roger/.profile file from floppy |
| cpio
-i "*.f" "*.c" </dev/fd0 |
Selectively
restore only the *.f and *.c files from floppy |
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Converts/copies
files to/from an output device. DD stands for Data Dump.
This command will NOT span across multiple
tapes. Common utility found on most versions of UNIX.
| Examples |
What
it does |
| dd
if=/dev/rmt0 bs=512k | cpio -icdmv |
Reads
the files off the tape device faster because of the blocking
factor (bs=blocksize of 512K or cache upto 1/2 MB at a time) |
| dd
if=rs6000.data of=/dev/rmt0.4 bs=1024 conv=ebcdic |
Copies
the data from the input file (if=rs6000.dat) to the output
tape device (/dev/rmt0). The rmt*.4 device extension means
output is written in 1600 bpi format. This creates an EBCDIC
low density tape, resulting in a 1024 byte blocked non-labeled
file. To extract this file on the AS/400, create a physical
file with a record length of 1024 bytes. Use the CPYFRMTAP
command to copy the file. NOTE: When
copying data from an EBCDIC machine, make sure your BLOCK
SIZE is set to 0 on the tape device |
| dd
if=unixfile.txt of=DOSFILE.TXT conv=ucase |
Copies
the data from the input file (if=unixfile.txt) to output name
(of=DOSFILE.TXT) and converts the source data to UPPERCASE
characters. |
| tar
-cvf- /u/roger | dd of=/dev/rmt0 bs=1024k |
Copies
the ABSOLUTE path /u/roger using the
tar utility. To speed this process up, these files are
piped to the dd utility using a cache buffer size of 1 MB. |
| dd
if=/dev/rhdisk0 of=/dev/rhdisk1 bs=5120b |
Copies
the raw physical volume named hdisk0 to the raw physical volume
named hdisk1. This represents a copy
disk utility. |
| dd
if=/dev/rmt0 of=/tmp/ascii_file conv=swab |
Copies
the data from the tape device (if=/dev/rmt0) and creates an
output file (/tmp/ascii_file) - which is BYTE swapped (conv=swab)
as it is being written out. This needs
to be done if your copying ascii files from a System V Unix
machine (unisys to the RS/6000) |
| dd
if=/dev/rmt0.1 of=/tmp/data1 cbs=242 ibs=3240 conv=sync,unblock |
Useful
when reading an ASCII file that is NOT delimited by a NL character. |
| dd
if=/dev/rmt0.1 of=/tmp/data1 cbs=147 ibs=2940 conv=ascii |
Will
read a record size of 147 bytes, a block size of 2940 bytes,
and convert the output to an ASCII file. |
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High-level
shell command for backing up mounted file systems in the rootvg
volume group. mkszfile
-f must be called prior
to mksysb in order to create the /.fs.size file that mksysb
uses to determine which files will be backed up.
8MM TAPE
DEVICE
An 8mm
tape drive is the preferred method of backing up your system
because that tape can be used to recreate the rootvg image
if one or more physical volumes fail. Each of the file systems
MUST have at least 500 blocks free when the mksysb backup
is made. The system will need some work space in each file
system when it is installing from a mksysb backup.
To utilize
the full 2.3 gb tape capacity...
- Set
the blocksize to 1024
- Edit
the /usr/lpp/bosinst/diskette/startup2
file
- Change
the following line from 512 to 1024.
/etc/methods/chggen -a rmt0 -a block_size=1024
- Create
a new install/maint diskette
MKSYSB
can create a BOOTABLE tape. Further, the data is archived in TAR
format. In order to look at the names of files backed up by this
command, perform the following:
- tctl
-f/dev/rmt1.1 fsf 3
- tar
-tvf/devrmt1.1
Example:
mkszfile
-f && mksysb /dev/rmt0
-f forces extending the /usr or /tmp file system
if not enough working space (8 MB) exists. This command should
ALWAYS succeed unless a tape has not been inserted into the archive
device (eg., rmt0), or the tape is either write-protected or has
defective media.
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Retrieve
information from archive device created with the backup
command. Default device is /dev/fd0. This command will read a
backup image spread across multiple tapes.
| Examples |
What
it does |
| restore
-Tvf/dev/rmt0 |
-T=table
of contents, -v=list the file name being
copied, -f=name of output device. Will list
the tape's table of contents. If you
forget to label the tape with the date that the tape was made,
use this command to report back the date this archive was
created. |
| restore
-xvf/dev/rmt0 ./usr/tmp/My* |
Restores
all files that start with "My" from the /usr/tmp
directory |
| restore
-xdvf/dev/rmt0 ./usr/tmp |
Restores
the directory named /usr/tmp from tape device |
| restore
-xvf/dev/rmt0 |
Restores
all the files located on the tape device that were backed
up using the backup command. |
| restore
-xvf/dev/rmt0 ./tmp/TestFile |
-x=extract
data from output device. Restores only the file named
./tmp/TestFile from the tape device. If the subdirectory /tmp
doesn't exist in the current directory, then that subdirectory
will be made prior to restoring 'TestFile'. |
|
1)
tctl
-f/dev/rmt0 rewind
2) restore -s1 -Tvf/dev/rmt0.1
3) restore -s1 -Tvf/dev/rmt0.1 |
1. Rewind
to the beginning of tape. 2. Review files on FIRST backup
image. 3. Review files on SECOND backup image)
Displays the table of contents for multiple backup images.
s1=specifies that multiple backups are on
the tape and that the restore command skips to the backup
specified by the number associated with the 's' option. The
0.1 for the output device (-f flag) means that once the tape
has been read, it will not rewind. If only the second backup
image was needed, could have just typed in: restore -s2 -Tvf/dev/rmt0.1 |
1)
tctl -f/dev/rmt0.1 fsf 3
2) restore -xvqf/dev/rmt0.1 ./unix |
If by
chance the ./unix file was deleted, go back to your install
tape and extract the file that needs to be restored. The first
three images on the tape are BOSBOOT, INSTALL/MAINT, followed
by the TOC (table of contents) image. |
| restbyname
-xvqf/dev/fd0 -Z /tmp/DISK.LIST |
Selectively
restore ONLY those files listed in file /tmp/DISK.LIS |
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Performs
consistency checks on a tape device. Primarily used to check tapes
written in backup format.
Example:
tapechk
2 ( Checks the first 2 files found on the tape device.)
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Probably
the easiest command to use when transferring files from one
UNIX system to another. This command
will NOT span across multiple tapes. Tar stands for Tape
ARchiver.
When
using this command while performing a SELECTIVE restore from a
tape device (eg;., tar -xvf/dev/rmt0 ./etc/motd), the tar command
will continue to run until the end of tape is encountered, even
after the file has been found. The error message tar:
directory checksum error (0 != 12345) Tar is an older utility
than cpio or backup/restore is
generated when an attempt is made to extract a file that is NOT
in tar format.
| Options |
What
it does |
| -c |
Writes
(creates) files (appends to archive device) |
| -x |
Extract
(read) files from archive device |
| -v |
Verbose
mode (displays names) |
| -f |
Device
name to use |
| Examples |
What
it does |
| tar
-cvf- * | dd of=/dev/rmt0 bs=128k |
Copies
all the files and subdirectories from the current directory
and pipes the output to the dd command for faster archiving. |
| dd
if=/dev/rmt0 bs=128k | tar -xvf- |
Use the
dd command to read the tape device for faster
archiving and pipe the output to the tar
command to restore the archived files. |
| tar
-tvf/dev/rmt0 |
List
the table of contents of the tape device. |
| tar
-cvf/dev/rmt0 /u/jones |
Copies
the jones account to the archive device named /dev/rmt0. |
| tar
-xvf/dev/rmt0 tmp/newdata /tmp/olddata |
Selectively
copies ONLY the newdata and olddata directories from the tape
to the current directory. |
| tar
-cvf- * | xargs compress -v > /tmp/tar.Z |
Copies
all the files from the current directory and compresses
them into the file named tar.Z. |
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Copies
from one magnetic tape device to another. This
command will work for copying multiple backup images from one
media type to another. It will continue to copy until two end-of-tape
marks are encountered.
| Examples |
What
it does |
| tcopy
/dev/rmt0 |
Displays
ALL the backup images and their size for the tape your currently
viewing. |
| tcopy
/dev/rmt0 /dev/rmt1 |
Copies
all the data from one media type to another until two end
of tape marks are encountered. In the example above, rmt0
could be a 8mm device and rmt1 may be a 1/4" tape device.
If the error message: tcopy: Cannot
open /dev/rmt?' is displayed, make sure
the destination device is not write-protected. |
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Command
used to fast forward a tape device (Tape ConTroL).
| Examples |
What
it does |
| tctl
-f/dev/rmt0 rewind |
Rewind
the tape device. |
| tctl
-f/dev/rmt0.1 fsf |
Move
tape forward to the second tape mark. The .1 on the rmt0 device
instructs the device NOT to rewind after performing the command.
Use this command to skip past unwanted
tape images - assumming there are multiple archive images
on the tape to skip past. |
| tctl
-f/dev/rmt0 retension |
Moves
the tape to the beginning, end, and back to the beginning
again. Used to retension the tape when
encountering multiple read errors on restore operations. |
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The
local host MUST be included in remote's hosts /etc/hosts.equiv
file. The local host and user name MUST be included in the $HOME/.rhosts
file at the user account at the remote machine.
| Examples |
What
it does |
| rsh
lanai -l roger "dd if=/dev/rmt0" | tar -xvf- |
Restores
files FROM a remote tape drive on a host named 'lanai' |
| tar
-cvf- * | rsh lanai -l roger "dd of=/dev/rmt0 bs=64k
conv=block" |
The tar
command will write it's output to the rsh command which pipes
the data to the remote host (lanai) and the tape drive (/dev/rmt0).
Specify -l <UserName> if the local
user is different from the remote user. |
| tar
-cvf- * | rexec lanai " dd of=/dev/fd0 bs=4096" |
Uses
the floppy drive device on node lanai to store files in tar
format. |
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