Re-use tape space issue_2
Hi all,
I work with VTL Solution. And all the time, when backup fails with error code "96", I can no longer re-use the space for other backup. The failed backup still using space on the virtual tape though it's not in the catalog; the space is lost !
This failed backup appears in my output in "NetBackup Management > Tape reports > Tape contents" but not in the catalog so I can not expire this fake image.
Is there any way (CLI or GUI) to fix that and re-use the space on the tape ?
bak-master:/ # cat /usr/openv/netbackup/version
HARDWARE LINUX_SUSE_X86
VERSION NetBackup 7.1
RELEASEDATE Thu Feb 03 17:33:27 CST 2011
BUILDNUMBER 20110203
bak-master:/ #
Below is the example of the tape with ID : 8A0084
Catalog output
Tape content output
FOR ANY MISSING INFORMATION, PLEASE TELL ME !!!
This is how it's supposed to work, regardless of whether it is a VTL or a physical tape library.
Please refer to the following excellent blog post:
http://www.symantec.com/connect/blogs/understanding-how-netbackup-writes-tapeBasically, for as long as there are valid images on the same tape, the 'gaps' left behind by the invalid ones (i.e., failed or expired images) will not be used by NetBackup for writing data.
Only when the last valid image on the tape has expired (i.e., there are no images left on the tape according to the catalog) would NetBackup go back and write the tape from the very beginning.In your case:
On 25/Apr/2014, you have 1 image fragment on tape 8A0084:
[ Image1 Fragment4 | Empty space ]Because the backup job succeeded, Image1 and all of its fragments on the tapes 8A007Y, 8A0082, 8A0083 and 8A0084 are considered valid, and are therefore stored in the catalog.
Then, on 28/Apr/2014, NetBackup attempted to use the remaining space on tape 8A0084 to store the first fragment of another image:
[ Image1 Fragment4 | Image2 Fragment1 ]Even though Image2 Fragment1 completed writing on tape 8A0084 using its remaining space, NetBackup couldn't find enough eligible tapes to write Image2's remaining fragment(s).
In short, because of status 96, the job did not complete successfully, and therefore Image2 is not stored in the catalog:
[ Image1 Fragment4 | Used Space ]The 'Used Space' is just that. Its occupied, but contains no valid image, and NetBackup would not use this space to append further backups. This tape would be considered 'Full' at this point.
As explained previously, only when Image1 Fragment4 has expired on this tape, could the whole tape - including the Used Space - be reused.The Catalog query only shows images that are 'valid' according to the catalog, whereas the the Tape Content report mounts and reads the tape to see what's actually in there.
An image fragment can be 'found' this way, but it does not necessary mean the image has to be recorded in the catalog as a valid image, or to be part of one.I would recommend focusing on trying to prevent status 96 from happening in the first place. With a VTL, you may want to consider presenting more virtual tapes to NetBackup. But if disk space is an issue, then... well that's another problem.
