Backup commands – usage and examples

Backup commands – ufsdump, tar , cpio
Unix backup and restore can be done using unix commands ufsdump , tar ,
cpio . Though these commands may be sufficient for small setups in
order to take a enterprise backup you have to go in for some custom
backup and restore solutions like Symatic netbackup, EMC networker or
Amanda .
Any backup solution using these commands depends on the type of backup you
are taking and capability of the commands to fulfill the requirement . Following
paragraphs will give you an idea of commands , syntax and examples.
Features of ufsdump , tar , cpio
ufsdump
1. Used for complete file system backup .
2. It copies every thing from regular files in a file system to special character and block device files.
2. It can work on mounted or unmounted file systems.
tar:
1. Used for single or multiple files backup .
2. Can’t backup special character & block device files ( 0 byte files ).
3. Works only on mounted file system.
cpio:
1. Used for single or multiple files backup .
2. Can backup special character & block device files .
3. Works only on mounted file system.
4. Need a list of files to be backed up .
5. Preserve hard links and time stamps of the files .
Identifying the tape device in Solaris
dmesg | grep st
Checking the status of the tape drive
mt -f /dev/rmt/0 status
Backup restore and disk copy with ufsdump :
Backup file system using ufsdump
ufsdump 0cvf /dev/rmt/0 /dev/rdsk/c0t0d0s0
or
ufsdump 0cvf /dev/rmt/0 /usr
To restore a dump with ufsrestore

ufsrestore rvf /dev/rmt/0
ufsrestore in interactive mode allowing selection of individual files and
directories using add , ls , cd , pwd and extract commands .
ufsrestore -i /dev/rmt/0
Making a copy of a disk slice using ufsdump
ufsdump 0f – /dev/rdsk/c0t0d0s7 |(cd /mnt/backup ;ufsrestore xf -)
Backup restore and disk copy with tar :

– Backing up all files in a directory including subdirectories to a tape device (/dev/rmt/0),
tar cvf /dev/rmt/0 *
Viewing a tar backup on a tape
tar tvf /dev/rmt/0
Extracting tar backup from the tape

tar xvf /dev/rmt/0
(Restoration will go to present directory or original backup path depending on
relative or absolute path names used for backup )
Backup restore and disk copy with tar :
Back up all the files in current directory to tape .
find . -depth -print | cpio -ovcB > /dev/rmt/0
cpio expects a list of files and find command provides the list , cpio has
to put these file on some destination and a > sign redirect these files to tape . This can be a file as well .
Viewing cpio files on a tape
cpio -ivtB < /dev/rmt/0
Restoring a cpio backup
cpio -ivcB < /dev/rmt/0
Compress/uncompress files :
You may have to compress the files before or after the backup and it can be done with following commands .
Compressing a file
compress -v file_name
gzip filename
To uncompress a file
uncompress file_name.Z
or
gunzip filename