Comparing files on backup set to whats on tape.....

[Jason_Cecchin]

I am trying to run a compare between those files on tape and whats actually on the disk of the server. We have reason to beliveve a couple of files got deleted/disappeared and we want to find out which ones. This could turn into a legal issue for the client so I need to have a quick but guaranteed way of getting the results within 24hrs.

I have tried using catdump but as per my post a while ago when another client needed a backup list the system truncated the dump before reaching the end of the catalog which makes it useless.. Same is happening here.....
http://forums.veritas.com/discussions/thread.jspa?messageID=4414223?

I have tried to run a verify but this doesn't seem to be doing what we want. To verify the verify job works they way I want I renamed a file (made it go missing) and changed a file (a backup copy). Problem is verify passed and didn't pickup these changes??? Does verify actually do a binary compare with a checksum of whats on media vs whats on disk or is it some tape integrity check????

Basically I need to compare whats in the backup on the disk with whats on the tape. This needs to be done before too many more files on the server change. With 42GB of data in over 143,000 files on the disk please don't tell me that I have to run a restore to alternate disk based media and then use a third party program to sort out the mess.!!!!

If I have to do this - does anyone know of a good inexpensive way of comparing two volumes easily.....

[ray_littlefie1]

Using a backup application is not the correct tool for what you want. You really want to enable file auditing capability by enabling Audit Directory Service Access on the domain policy and individual file auditing on the file volumes. If you want to protect data from being maliciously being deleted you would need the backup exec add-on CPS.

However, to answer your question- A Verify operation only reads & compares checksums generated and written to tape at the time of the backup. It verifies that the tape is still readable. It does not look to the source data and compare to what's on tapes.


You would need to restore to an alternate volume and compare the contents to the 'live' volume. A resource kit tool called Robocopy.exe might help:

robocopy /mir /L might work.

This command would mirror the live data path to the restored data path; however using the /L switch would only list changes (not actaully perform the mirror) so the screen would list all the proposed changes (files added, modified and deleted since the backup).

[Jason_Cecchin]

You are totally correct that a backup program is not the best software to deal with this issue. Unfortunately this is a one off occurrence and not likely to be repeated.

We will be discussing the problem and preventing its occurence with the client. They decided auditing was not required as it was an admin overhead and didn't contribute to a solution if stuff was deleted. (It would be hard to filter legit and problem issues unless someone actually noticed it)

You are correct that CPS (don't know much about it) or a checkin/checkout version control style solution would be the answer to this problem and making future remedy much easier.

Thanks for the info about robocopy. I have to admit its not one of the first tools I think of.... Iand I didn't know it could do what you described. ts just a pity I have to restore ALL the data and do the compare in the first place - oh well - let me stop me whining and lets get to work making it happen.Message was edited by:
Jason Cecchin
Typos.....

[Ashutosh_Tamhan]

Hello Jason !

You could check if you have the backup job logs of those backupsets which you want to compare. But provided that the setting under Tools - Options - Job Log - Display detailed information about files was set before the two backups were run, in order to get a detailed job log.

Then you could use a third party utility to compare strings between the two job logs! :)


Regards,
Ashutosh

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