FAQ:What versions of GNU Tar are Amanda-compatible?

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Amanda makes some heavy demands of GNU tar (sometimes known as gnutar or gtar), so some versions of tar will not work with some versions of Amanda.

Note that many vendors backport fixes to earlier versions. For example, RedHat's tar-1.14 contains the fixes that were published in tar-1.15.1.

 Amanda-2.5.1p2 and earlierAmanda-2.5.1p3 and later
1.14.xCommonly Bad3Commonly Bad3
1.16 and aboveBad4,5Good
1.24 and 1.25Bad6Bad6


Tar 1.13.19 sets return code 2 for some infrequent conditions even with --ignore-failed-read option. This results in Amanda thinking the total archive is bad, and drops the complete archive. Those conditions are very rare on a quiet filesystem.
Tar 1.13.9x has changed the format of "tar -t", resulting in amrecover not able to use the indexes.
Tar 1.14.x writes good archives, but when restoring, it has trouble with sparse files: the sparse file itself, and all files after it cannot be read anymore. But you can read the archive with a good tar version (the tar images produced are fine -- it just can't read them correctly). If you are using Red Hat Enterprise Linux, this has been fixed by a backport; Please make sure you are using the most recent RHEL tar package and, if needed, use the --nodeps flag when installing Amanda using rpm.
See http://marc.info/?l=amanda-users&m=117621620031671&w=2. Tar 1.16 returns 1 when it sees size of a file changes. It's a new behavior that breaks Amanda prior to Amanda-2.5.1p2. See also Re: [Bug-tar] --ignore-failed-read not applied to files changing as tar reads them.
The format of the --listed-incremental snapshot files changed after tar 1.15.1. Among other differences, the entry separator used in the file changed from a newline to a null byte. Because of the way amanda prior to amanda-2.5.1 reads in these files, this would cause backups and estimates of incremental dumps to behave improperly or fail.
Note: The table above says that amanda-2.5.1p2 is required if using tar > 1.15.1. This particular issue was fixed in amanda-2.5.1 (but 4 still applies).
These versions have a fatal flaw which causes backups to only contain the root directory and no files. See http://www.mail-archive.com/bug-tar@gnu.org/msg02999.html , http://thread.gmane.org/gmane.comp.sysutils.backup.amanda.general/37932 , and http://www.mail-archive.com/bug-tar@gnu.org/msg03187.html .

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