Hi,
I noticed something in my backup enviroment.
We have just LTO4 Tapes (800GB/1.6TB) for backup.
Many tapes are with 430-480GB Full Multiplexed. How can be a LTO4 Tape with 430GB Full???
Regards
Marius Demeter
NetBackup only marks a tape as full when it is 'told' to do so by the operating system, which is told by the tape driver, which in turn is told by the drive.
If there is an issue, the most likely cause will be one of those.
Kindest regards,
Martin
:) we bay this tapes from HP Shop from Austria.
I will try to get more info.
Regards
Marius Demeter
You may want to try a full erase of the tape, using the tape drive manufacturer's utilities. Then try your backups again. In almost all cases, this solved my issues, short of grey market tapes or faulty tapes, in which I usually can return as defective.
Hi,
What kind of performance are you seeing on the backups that occupy the "partially" full media.
Erase the whole media and backup again. Is it for all tapes which you have?
@teiva_boy: Where can I find a utility to full erase a tape?
I have "HP StorageWorks Library and Tape Tools" but i can't erase a tape with this tool.
It is not good the "Long Erase" from NetBackup console?
@shrisai: I have quick erase all tapes ...but is tha same. This problem is not for all tapes ...but is for many. Come for tapes with 185 mounts und also for tapes with 25 mounts.
Can be the drives?
Regards,
Marius Demeter
There may be software and hardware compression taking place. This may be why you are seeing the difference in the amount of data on the tapes.
Even though the tape only states that it has 430 gig of data on the tape it still could be full. You can see this information when you run the "available media report". It will show you if the tape is full and how much data is on the tape. The amount can vary fairly significantly depending on what type of files your backing up.
A backup of very large files will usually see a decent compression rate while a backup with many small files will not compress nearly as much. Hope this helps!
I don't solved my problem. On the last full backup i have one tape (LTO4) with 285GB Full Multiplexed. How can happen something like that?
I have try to "long erase" but not help.
All my full multiplexed tapes are between 400-600GB. Before was 700-900.
It can be from the drivers? The drivers are 3 year old and are used every day.
The tapes can't be while i have try also with new tapes ...and the same problem.
What do your barcodes say for the type of tape?
Do they end in L4? or maybe L2 or L3?
NetBackup only marks a tape as full when it is 'told' to do so by the operating system, which is told by the tape driver, which in turn is told by the drive.
If there is an issue, the most likely cause will be one of those.
Kindest regards,
Martin
