AI files content (VERY URGENT)

K

kennykilla

New Member
Hello!
I have a very urgent question.
I have a restored from tape database (Progress 10.1B) and many AI files that i have to roll forward. But i have to roll not all AIs but until some moment in time when database crashed. My newbie question is how to determine date/time of transactions contained in these AI file?
I know if try to roll forward in wrong order i can break my database.
And also how i can determinte date/time of last transaction in my base to make sure there is no gap between it and AI files.

Thanks in advance!
 
Are you trying to roll forward to a particular point in time before the crash or just wanting to make sure that you roll forward everything?
 
I am trying to roll forward to a particular point.
I'm afraid to roll AIs in wrong order. Is it possible?
And is it ok if the database was last changed at 04:26 and the after-image file was started as i know at 03:45? Will Progress roll it ?
 
Are you saying that the current time-stamp on the database is *later* than the last timestamp on your ai files? This is after you have restored your backup?
 
Yes. But i'm restoring not with probackup/prorest. The database was just stopped and saved to tape as a directory. Our database size don't let us to use probackup.
 
Err, AI only works against a backup. One needs to take the backup, accumulate the AI files, have the problem, restore from the backup, and then apply the AI files. If all you have is a periodic tar or cpio of the database, that won't do you any good with the AI files.

How old is the backup aka copy? I hope the database was down when you made the copy.

Why does the DB size matter for probkup? Meaning it takes too long? If so, have you considered doing a probkup to disk and then rolling the backup file(s) out to tape. That is very fast and the database can be back up again quickly.
 
Yes, of course the DB was down when written to tape.
Do AIs are really useless when we talk about directory copy (not probackup)?
 
I'm not the DB expert, but that is certainly my understanding.

I take it that you have never actually tested your backup and restore before?
 
You cannot damage your database by applying ai files out of order.

All that will happen is that you will get a warning message about the ai file being the wrong one. It will tell you that you provided extent sequence 123 when it expected extent sequence 321.

Depending on Progress version and the relative dates of the backup and the extent you might also get a message about timestamps not matching.

In neither case does attempting to use the wrong ai file cause a problem. You just try again. (Hopefully with the correct extent.)
 
To roll forward to a point in time use:

rfutil dbname -C roll forward endtime yyyy:mm:dd:hh:mm:ss -a aifile

You can specify the end time on every extent if you are not sure which one contains the end time that you are looking for.
 
You can use OS copies of databases with after-imaging. But it is trickier to get it right. And I'd want to test it carefully before I counted on it working.

Just how big is this database that is too big to be backed up with probkup?

And if it is so big how do you justify not testing your recovery process for 3 years?
 
Well, you might want to consider a small dose of some expert guidance to get you on the right road in the future. Fortunately, The Expert in this sort of thing has joined the conversation, so he might be able to help you make as much as you can out of the current problem, but clearly there is an issue here of getting some guidance on sound policies, setting up the right procedures, implementing some tools, and the like which will put you in the best shape for the next incident.

It might be useful to tell us something about your current procedures in terms of when these OS copies are made relative to the AI files and how that works in terms of timing and such. It is likely to be critical for what it is possible for you to do from here.
 
Tom,
As you wrote, it is possible to apply ai files on OS backup.
Can you elaborate on this, as i m new to progress and thought it could be applied on backup files created by probkup.
Thanks.
 
Yes you can apply AI files to an OS backup, we do it often. 2 important items, you must learn about the rfutil command with the sequence option and know what AI sequence was in use when the database backup was taken.
 
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