You can check Redbook sg246147 "Using TDP for MS Exchange Server"

Chapter 2.3.1 "Policies and management classes" ; there is really good and in 
depth explanation of how the backup works.
I didn't fully understand it when I read it, but after I setup test environment 
and tried it everything cleared up.


Joe Crnjanski
Infinity Network Solutions Inc.
Phone: 416-235-0931 x26
Fax:     416-235-0265
Web:  www.infinitynetwork.com



-----Original Message-----
From: Fought,Tom [mailto:foughtt AT OCLC DOT ORG]
Sent: Wednesday, November 05, 2003 12:50 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: TDP Exchange Copy Group Definitions


Thanks Del.
Now that I understand that, how about commenting on
each of the copy group items in my example, supply a
definition which is easily understandable, an example
would suffice. I have read the redbook and I am still
confused.
Tom

-----Original Message-----
From: Del Hoobler [mailto:hoobler AT US.IBM DOT COM]
Sent: Wednesday, November 05, 2003 12:43 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: TDP Exchange Copy Group Definitions


Tom,

First... I am assuming you are referring to
Data Protection for Exchange version 2 or higher.
Version 2 and higher use standard TSM policy management.
(Version 1 used different policy management.)

These settings basically mean that you will be
able to restore any full backup for that last 90 days
as long as there haven't been more than 90 different
backups within that timeframe.

These settings are OK... but if the intent is to
keep any backup for 90 days...
... the settings should be more like this:

   Versions Data Exists     NOLIMIT
   Versions Data Deleted    NOLIMIT
   Retain Extra Versions    90
   Retain Only Version      90

This makes it so that no matter how many backups
you take during the timespan... they won't
expire earlier than 90 days.

Thanks,

Del

----------------------------------------------------

> Could someone with TDP Exchange experience comment on what
> the following copy group definition for TDP Exchange clients
> would mean for tdp object retention?
>
> Versions Data Exists 90
> Versions Data Deleted 90
> Retain Extra Versions 90
> Retain Only Version 90