dump (software)

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dump (from the English to unload or tilt ) is a traditional Unix program or a command , which for data backup of filesystems can be used. Under Unix System-V the program is called ufsdump . It has been adapted to various file systems that are similar to UFS , especially under Linux .

dump works at the block level , i.e. below the file system abstraction like files or folders. A file system can be backed up to tape or another hard drive using a dump call . It is often used for securing in the network via the pipe of an SSH connection. Compression programs such as LZO , gzip , bzip2 or xz are used, which differ in terms of their degree of distribution, compression rate and operating speed.

The first version of a dump program appeared in AT&T UNIX version 6.

Before file system snapshots were possible, dump had the advantage over common programs such as tar or rsync that the attribute of the last access was unchanged, since this can only be changed via file system access.

When backing up with dump , the file system must not be in use, since changes to the file system would lead to inconsistencies. You can avoid this problem by using file system snapshots.

The counterpart to dump is the restore program , which is used for restoring.

use

dump [-0123456789acLnSu] [-B records] [-b blocksize] [-C cachesize]
[-D dumpdates] [-d density] [-f file | -P pipecommand] [-h level]
[-s feet] [-T date] filesystem

dump -W | -w

See also

Web links