Leonard Berkowitz asks:

>Is there an online backup product/process that captures transactions that occur
>during the backup, after the sync point, and ,if/when the tapes are used for a
>restore, on the same system or another system, applies those transactions?
>
>In other words, the state of the files at the end of a restore is the same as
>the files at the end of the store.

I'm not sure if I am reading this question the right way compared to the
other answers, but let me reply according to my read. The operative words
that I picked up on were "after the sync point".

The real question is what determines the "end of the store"? At some
point in time before the store process finishes, it must post online
activity to the archive. This process also takes time, so there is
some elapsed period between when the "logging" is finished and when
the "store" is finished.

That point where the logging is finished can be defined as the "sync
point". The sync point may also have additional states to it: either
the data in database and files can be consistent at that point in
time (logical consistency), or it may not be. If one chooses to try
to be logically consistent at the sync point, then a bunch of additional
factors come into play, such as attempting to quiesce I/O to all of
the files and databases involved within transactions. Without logical
consistency, the sync point could be some arbitrary point where the
backup product says "enough" and completes the backup.

That being said, the point after the "I'm done logging phase" or the
"... captures transactions that occur during the backup, AFTER THE
SYNC POINT ..." (emphasis mine because of the way I'm reading your
question) does not have transactions captured using the traditional
backup products. Transactions happening after that point will not be
on the current backup.

Up to this point, I've not talked specifics. Gonna do that now, so

<plug alert>:

There is one exception to this and that is ORBiT's Delta Backup
Technology. In order to make Delta work, the "logging" process, if you
will, remains active between backup runs. So, you can capture transactions
"after the sync point" of the backup onto a subsequent backup. That is
not (again, the way I read the question) entirely what you're asking for,
but it indirectly does what you're asking about.

<end plug alert>

Perhaps I should now put my best consultant's hat on and ask the
question a different way:

You state that you want to capture transactions after the sync point:
what exactly is the problem you're trying to overcome?

If I completely misread the question, then the other answers in fact
are correct and the length of this post is to make my wirt count. ;-)


Regards,



M.

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