3

I backup my data every day on tape using one drive DAT HP Storageworks DAT 160. I use one tape for every day and I turn them weekly. Every monday I check one tape randomly recover some files saved on it.

I know that when data is saved on tape, the driver and backup software check data integrity, but I wonder if a manual check of some data saved has a sense or not. I re-use these tapes many times and I would be sure data are safe.

HopelessN00b
  • 53,795
  • 33
  • 135
  • 209
maxim
  • 89
  • 1
  • 8

2 Answers2

3

Restore tests are a good thing, and you should definitely put forth the effort to manually test your backups. If you don't have backups you know are good, you don't really have backups, and I have seen sad cases where backups that validated as good were not restorable, so better safe than sorry. As they say, trust but verify. If you do full system backups, make sure you can do a full system restore as well, not just a file backup, and likewise for other data types, like databases or VMs (provided you have those in your environment.

Once a week is on the high side as far as the frequency of backup tests, but better too often than not often enough. I do mine about once a month, and test file restores, database restores, system restores and virtual hard disk restores, since we have all types of backup and they're all expected to work.

HopelessN00b
  • 53,795
  • 33
  • 135
  • 209
  • 1
    -1. The OP does not ask about restore tests but about tape integrity checks. Restore tests - to make sure that all the stuff you think should be there is there etc. is totally different from oring half a dozen files to make sure the tape is not corrupt. – TomTom Dec 17 '12 at 10:59
-1

Check your backp softtware for a validation routine.

In general, restoring to SEE THE CONTENT is ridiculous - you can trust checksums to work well enough that a file that does not show an error contains the same content that you had at backup. You basically waste a LOT of time.

Tape integrity checks should be a semi (need to replace the tapes in the drive) automatic function of your backup software.

TomTom
  • 51,649
  • 7
  • 54
  • 136
  • This is dangerously bad advice. You could save even more time by not doing backups at all. – HopelessN00b Dec 17 '12 at 10:57
  • WHy? Normalyl you have multiple Level of checks. If the tape validates successfully in the backup Software, that means you have the in tape checksums AND the Software Level checksums intact. How much more do you Need to check that the TAPE is not corrupt. THis is not against making restore checs to make sure your Approach works, but I have not checked tapes for "is the tape ok" by making single fie restoreor ge and neve had a problem – TomTom Dec 17 '12 at 10:58