Disc dead - backup earased (bug)

[Brian]

Version 2.7.0.329

When a scheduled task tries to backup over my LAN and the PC on the other end is switched off AIS simply does nothing.

But yesterday it shown behavior that can be qualified as a bug I think.
One of my HDs is old. In still works fine for light loads. But occasionally it just 'vanishes'. Meaning it doesn't show up as a drive until the next reboot.
AISBackup tried to backup that drive and somehow 'saw' the drive because it didn't just skip the scheduled task.
It pruned the previous backup until it was completely empty.
(I only keep one generation)
So it looks like AISbackup did see the drive but couldn't read it so it assumed the drive was empty.

I hope a future release can solve this behaviour because when a HD dies I/we need AISbackup the most
I hav eno idea how hard such a thing is to program because it can't really be tested. Not many people are so lucky like me having a half dead drive
Perhaps writing and reading a very small test file is good test.
Just a thought...

[Barry]

There should be a way to fix this problem by getting AISBackup to open the backup from the backup media rather than the local database, however the style of backup will also have to be changed:

The process involves removing the backup from the list of backup jobs and then reinstating it as a ‘Networked External Drive’ backup – it does not matter if the disk is not an external drive.


Instructions:

Manage Backup / Remove Backup Job From List / Yes / Keep

Tools / Open Job From Backup Media / Locate the backup file on the network and Open / Yes to reinstate / Yes to Is this a networked external drive? / No to Restore Only

Barry

[Barry]

I just re-read your post and realise I did not answer it.

The problem you have is Windows sees the remote drive, even though it has died. AISBackup then sees a drive as if it has been formatted and there is nothing on it at all. As all the files on the disk ‘have been deleted’ AISBackup correctly marks them as deleted and in a one-session backup, removes them from the backup – i.e. not a bug.

There seems to be a bug in Windows in that it is making the dead drive available on the network and showing it as empty, at least this is what AISBackup is seeing. If this happens regularly on your system I would like to know what Windows Explorer sees on the drive, I would also be interested to know what AISBackup sees in the Manage Backup / Add Remove Files, for example does the disk volume name show as ‘None’? Which means the drive is not present. I am not sure if the problem can be duplicated manually so hat a work-around can be made.

If the data on the disk is not too transient, or not many files are deleted, then the backup type could be changed to Generation / Keep 1 Generation, the if the drive goes AWOL then the backup will not be pruned – but then again neither will the deleted files.

If a sensible way of detecting the disk is missing rather than empty then a work-around could be made. Writing and checking a file cannot be done in case the disk is read only (some can be physically marked read only).

Barry

[marbit]

I had a similar problem: The files to backup are on a NAS. Due to a reboot of the domain controller, the NAS lost connection to the active directory. As a consequence, all users were denied access to the shares on the NAS. The explorer reported that access was denied. AISBackup didn't report an error, but considered all files as deleted and erased the entire backup. In my opinion, this must be a bug. There was no empty drive, but a drive to which access was denied. I don't dare to think about what might happen if a source disk becomes faulty and AISBAckup is scheduled to backup it automatically - it might just erase the backup and all data would be lost.
As a simple safeguard against this, I suggest that AISBAckup shouldn't do anything when ALL files in the source are deleted - this is surely not an everyday situation and shouldn't be handled automatically.
Martin

[Barry]

The code has been changed in version 2.7 which should be uploaded soon. Thanks for the post - as the access denied has not been tested - just the unavailable disk.

Barry