Joshua,

You are talking about doing a very dangerous and unreliable thing...
...and it probably won't work like you think...
I don't want to get into a lot of detail on the internals
of how Exchange Server works but I will try to explain why...

The Exchange server database is always in an "unstable" state
until the Exchange Server is completely shutdown.
(When the Exchange Server is down, all databases and logs
are written to disk...and not until then.)
So, taking a low-level disk copy will almost always produce
a copy of the Exchange Server files in an unstable state.
Some data has been written, some hasn't.  Only the Exchange Server knows.

The Exchange Server keeps as many things as it can in memory
and does efficient disk writes using lazy write technology.
(Minimize the disk head movement...)
Exchange Server 5.5 SP3 especially takes advantage of this
as many of you know...that is, it will eat almost all of your
available RAM to fit in as many database and log pages
as it can. For more details on Microsoft Exchange internals,
see your Microsoft documentation.

If you could bring down your Exchange Server, then do the copy,
then restart your server... then you would be fine...
But there are not to many people that have that luxury today.

Thanks,

Del

----------------------------------------------------
Del Hoobler
Del Hoobler
IBM Corporation
hoobler AT us.ibm DOT com


"Joshua S. Bassi" <jbassi AT GLORYWORKS DOT COM>@VM.MARIST.EDU> on 09/13/2000
01:27:28 PM

Please respond to "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>

Sent by:  "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>


To:   ADSM-L AT VM.MARIST DOT EDU
cc:
Subject:  ESS FlashCopy & MS Exchange



All,

I have a customer interested in purchasing a Shark to
store their Exchange data.  Today they are using TSM
and TDP for Exchange to backup their servers.  That is
working well for them, but they are interested in using
the ESS FlashCopy feature to make periodic (4-5 times
daily) copies of their Exchange data. They want this
high frequency due to the fact that they have had many
issues with corrupted data (I know, but let's not go
there :-)

If for some reason they need to restore their server,
they would like to use the latest FlashCopy image to
perform a quick restore.

My question is:  how would this work?

What would happen if I took a raw copy of the Exchange
mail store and then restored that copy outright?  What
would happen with the Exchange logs/journals?  Would I
need to reply the journals just to get Exchange to come
up? Or maybe I could use TDP for Exchange to continuously
backup the logs throughout the day to be used in the
event I restored the base Information Store from the
latest FlashCopy snapshot?


--
Joshua S. Bassi
Joshua S. Bassi
Senior Technical Consultant
Symatrix Technology, Inc.
jbassi AT gloryworks DOT com