On Thu, May 01, 2003 at 03:13:12PM +0200, Gregor Ibic wrote:
> we have a DLT2000 15/30 and we backup a single image
> the backup spent about 1.5 hour for 5GB
> then we recover a file from the tape and it needed the same time for recover
> also, even when the file was already restored, the tar continued to read the
> tape till the end.

As someone mentioned earlier, yes the behavior of tar is to read the entire
tar file.  If the DLE containing your file is 5GB, then tar will read the
entire 5GB.

Why is tar's behavior this way?  Well in part, because in a single tar file
there could be multiple copies of the same file.  Tar can not be sure there
isn't another one lurking later in the tar file.  That is the nature of tar.
Amanda has no control over that.  Amanda does not use this capability (to my
knowledge), but tar doesn't know that.

However, you know that amanda will only place one file in the tar file.
If the time is so important, monitor the recovery.  When all you want is
recovered, interupt amrecover.

If you don't like tar's behavior and have a suggestion, I suspect the GNU
developers responsible for tar have a wishlist somewhere.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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