Red Hat Bugzilla – Bug 176641
tar 1.14 doesn't extract sparse files correctly, breaking amanda
Last modified: 2007-11-30 17:07:09 EST
+++ This bug was initially created as a clone of Bug #154882 +++ Description of problem: Amanda uses the --sparse option to tar when creating backups. Tar 1.14 is known to have problems with extracting sparse files (see http://lists.gnu.org/archive/html/bug-tar/2005-02/msg00003.html). Version-Release number of selected component (if applicable): tar-1.14-4, amanda-2.4.4p3-1 How reproducible: Always Steps to Reproduce: 1. /bin/tar --create --file /dev/null --directory / --one-file-system --listed-incremental /var/lib/amanda/gnutar-lists/euclid.math.ohiou.edu__0.new --sparse --ignore-failed-read --totals --exclude-from /var/log/amanda/sendsize._.20050414123909.exclude . Where /var/lib/amanda/gnutar-lists/euclid.math.ohiou.edu__0.new and /var/log/amanda/sendsize._.20050414123909.exclude are both empty files. Actual Results: The tar output claimed I had 1.2TB on a 20GB partition Expected Results: It would have told me I was using about 3.5GB of my 20GB partition.
I guess your /var/log/lastlog is a big sparse file. Fixing tar is not efficient until lastlog size is allright.
On a RHEL3: $ rpm -q tar tar-1.13.25-13 # Create a sparse file: $ dd seek=500000 count=5 if=/dev/random of=test 0+5 records in 0+1 records out $ ls -lh test -rwxrwxr-x 1 bnocera bnocera 244M Jan 17 16:13 test $ du -hs test 28K test # Create the tar file $ tar cvfS test.tar test test $ ls -l test.tar -rw-rw-r-- 1 bnocera bnocera 20480 Jan 17 16:15 test.tar # Show the totals $ tar cvS --file /dev/null --totals test test Total bytes written: 20480 (20kB, 20kB/s)