www.aiscl.co.uk

For the first time, I've attempted a massive restore from a massive AISB backup, and I've seen something I'm dubious about. I've stewed on this for a several hours trying to see the logic in it, but I'm stumped. Maybe I've done somthing wrong?

My issue is this: each file gets restored many times. This caused the restore to take a very long time. For example, my restore took 5 hours and restored all of the big files 10 times. It seems to me this restore could have taken only one half hour.

My backup has many sessions and each session contains many very large (x00Mb) files that change daily. If I restore a file from a session that has ten sessions behind it, then I restore that file eleven times!

I understand that the end effect of all this does produce the desired result, but it my case (a wide and deep backup) it takes many times longer that necessary.

I don't see why AISB doesn't simply look for the most recent session that contains the file and restore only that one. What's the point of restoring all the earlier versions, only to overwrite each one?

Best regards,
Kirby

We recently noticed a problem with the beta versions of AISBackup 229, 230, 231 and 232. The deleted status of each file was incorrectly reset, in other words AISBackup thinks that all versions of each file on the backup exists, this has the knock on effect of incorrectly restoring all version of the files, even though only one version should exist in the chosen session. The next version of AISBackup will correct the Backup Contents File, but there is no way to determine the date an actual file was deleted, although we can accurately set the ‘deleted’ status of changed files.

If you have an urgent requirement to restore from your backup we will make the updated version of AISBackup available to you now, although we expect to upload the next version within a day or two.

An updated copy of AISBackup.exe can be downloaded from here until the next version is uploaded, just replace the existing AISBackup.exe.

http://www.aiscl.co.uk/jan05/aisbackup.zip

This version will automatically update the corrupt Backup Contents File for each job.

Barry

Barry,

Your explanation mostly makes sense to me. Bugs I understand -- I generate plenty of them myself!

I was with you up to:

>>...but there is no way to determine the date an actual file was deleted, although we can accurately set the ‘deleted’ status of changed files<<

and there I lost you. You seem to be saying there will be a subtle loss of data in the backup, is that correct? If so, will there be any noticable effect?

In any case, I can wait for the next version since I rarely (hopefully) have to do massive restores.

-Kirby

Hi Kirby

Following the problem with the beta program here is an explanation of the Deleted flag which was re-set.

AISBackup marks a file in the backup as deleted when it is replaced by a new version, these files can be correctly marked as deleted by AISBackup.

Files that were really deleted can only be marked as deleted again the next time AISBackup is run. Example:

A file called c:\autoexec.bak exists on the PC before the first backup session, a backup is run three times and then c:\autoexec.bak is deleted from the PC, another two backups are run, When AISBackup is working c:\autoexec.bak is labelled as created in session 1, deleted in session 4. After running the affected beta version with session pruning enabled the file is marked as ‘not deleted’, in other words c:\autoexec.bak now exists in sessions 4 & 5 (clearly incorrect). After running a new backup session with the fixed version AISBackup will mark c:\autoexec.bak as deleted in session 6, i.e. the new backup session.

Barry

Got it. That's pretty darn subtle. I doubt that I'll ever tangle with it, but it's good to know.

Thanks for the super response to this problem! Viva La ASIC!!
-Kirby

Beta version 2.0 (build 233) of AISBackup has been uploaded, this will correct the Backup Contents files of backups made with beta builds 229, 230, 231 and 232. If you have time please re-run a large restore and let us know the outcome.

http://www.aiscl.co.uk/downloadaisbackup.htm

Thanks

Barry