>> I browsed the fine manual but was hoping to gain a little insight from
>> other experiences.  I understand that it's no longer a streaming
backup,
>> it's a VSS software snap.  Does anyone know how long the Exchange DB's
>> are in a guessed state?

Do you mean quiesced state?
Writes to the disk are suspended for less than 10 seconds
(Microsoft requirement), but Exchange continues to be able
to service requests.


>> Does it depend on the DB size or does VSS get a
>> snap and then tsm backs the snap?

Once a snapshot is created, there is logically a "static" copy
of the volumes that the the database and logs are on. At that point,
TSM will perform the integrity check (Microsoft requirement)
and then back the files up to the TSM Server. The integrity check
and backup is performed on the snapshot volume.
The VSS Provider that you use will determine what the physical
representation of that logical volume snapshot is.
If you do not install a VSS Hardware Provider from the disk
vendor that you are using, the Microsoft "in box" VSS System Provider
is used. The the Microsoft "in box" VSS System Provider is a
software-based, "copy-on-write" implementation.


>> If the DB is guessed for the duration
>> of the backup then maybe it makes sense to backup just the passive
dags.

Again, I assume you mean "quiesced" state...
Microsoft and IBM recommend that you perform the backup from the
passive DAG copies to help "offload" the hit to the production servers.


>>
>>
>> Any thoughts or insight would be great!

Take a look at this. It is a blog that I wrote that gives you
some links that help explain what VSS is and how TSM works with VSS.

https://www-950.ibm.com/blogs/tivolistorage/entry/ibm_tivoli_storage_flashcopy_manager_and_windows_snapshots8?lang=en_us


>>
>> Regards
>>
>> Charles


Thanks,

Del

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