SureStore DAT24 Restore Problems

[Clive Doubell]

Hi there

I just made some backups of digital video material on my trusty HP DAT24 with DDS3 tapes. Each section of video that I backed up consisted of between 40 and 50GB. This means that each backup would span between 4 and 5 DDS3 tapes. I cleaned the machine regularly during the backups and I used brand new tapes.

I run WIndows 2000 Professional SP3 and I used the backup program that comes with Windows.

Now when I needed to restore the video material I found that the restore would work perfectly until it hit about the middle of the third tape in the series (of 4 or 5). An error message then appears that says "BACKUP ERROR: This media needs to be erased to be used".

Even if I tried to restore the last of the backed up files, that I'm sure would be on the last tape, say tape 4 or 5, the same error would appear.

Well I don't understand this error message as it seemed that the backup procedure ran without a hitch, and the last thing in my mind when restoring data would be to erase the tape that I'm restoring from.

I tried the same procedure on about 4 of the backed up tape sets, and lo and behold, the same error came up every time, exactly when the machine was busy with tape no 3. So for me this means that it is unlikely that it is a tape media error. It looks more like some limitation on total file length or something like that. I didn't hit this problem ever before because I never before had the need to make a bachup that spanned more than 2 tapes. Now that I made backups that spans more than 3 tapes it seems there is some restriction built into the software or hardware.

I would appreciate if if I could get some advise concerning this matter, as I obviously need this video material that was backed up very urgently.

Many thanks.
Clive

[Dave Dewar]

Hi Clive,

This does not sound like a tape drive issue as you pointed out. Since you are backing up digital video (already compressed format) you will be operating at native capacity and so should expect to see about 12GB per tape. The appears to be what you are seeing 40-50GB = 4-5 tapes.
The mid point on the third tape would be about 32GB in that case and I vaguely remember some windows filesize etc limitations around this point, Ithink it was FAT32 format. However, presumably you have a 50GB file on your hard disk as your backup source so you must be using NTFS format so it might be a filesize limitation in NTbackup.
I would suggest a microsoft knowledge base search on file size limitations might give you some ideas.
40-50GB files are extremely large :-), is it not possible to break up the digital video files into smaller chunks like they do on DVD's? I thought all video editing software supported this sort of feature.

Cheers,

Dave Dewar.