A full backup that has a dependent differential can be expired, but will
not be deleted.  This means that a full backup that is beyond the retention
criteria will not be visible, but will be available for restoring
differentials.  As others have noted, fulls and differentials are managed
by the same management class, so each will appear as just another version.

In Wanda's example,

> The question is, if retextra is 15 and retonly is 15, and you take one
full NDMP backup followed by 20 diffs, does anything roll off?
> How many fulls and diffs do you have left in the DB?

The full is expired, but not deleted.  The first five differentials are
expired and deleted.
You will have 15 restorable backup versions.  All versions happen to be
differentials, but the full is still there, ready to go when you want to
restore one of the differentials.

In David's example,

> 1)      [management class/copygroup] with retonly=15 and retextra=15
> 2)      it received data from a backup node (NDMP) process
> 3)      the NDMP runs a full backup once every six months
> 4)      the NDMP run an incremental monthly on the months a full is not
run

Again, you will have 15 restorable backup versions.  Each version might be
a full or might be a differential.  The oldest versions might be
differentials with no visible full, but the full is still available.

Mark Haye (马克海), IBM TSM Server Development, mark.haye AT us.ibm DOT com,
8/321-4403, (520)799-4403, 0N6/9062-2, Tucson
Professional programmer.  Closed source.  Do not attempt.


"ADSM: Dist Stor Manager" <ADSM-L AT vm.marist DOT edu> wrote on 02/22/2012
09:59:23 AM:

> From: "Prather, Wanda" <wPrather AT ICFI DOT COM>
> To: ADSM-L AT vm.marist DOT edu
> Date: 02/22/2012 10:10 AM
> Subject: Re: [ADSM-L] What if (NDMP)
> Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT vm.marist DOT edu>
>
> I'm glad David asked this question, because I have the same one, as
> I have been digging around in the backups table trying to figure out
> what goes on.
>
> The question is, if retextra is 15 and retonly is 15, and you take
> one full NDMP backup followed by 20 diffs, does anything roll off?
> How many fulls and diffs do you have left in the DB?
>
> Does the retextra/retonly apply just to the fulls, or just to the
> diffs? Both? How?
>
> Wanda
>
>
> -----Original Message-----
> From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On
> Behalf Of Christian Svensson
> Sent: Wednesday, February 22, 2012 10:27 AM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: [ADSM-L] SV: What if
>
> Hi,
> The Full Backup and Inc Backup are the same object for TSM.
>
> That mean if you backup the Full Backup with Managment Class A then
> backup Incremental with MG Class B, TSM will then change the FULL
> backup to MG Class B.
>
> Best Regards
> Christian Svensson
>
> Cell: +46-70-325 1577
> E-mail: Christian.Svensson AT cristie DOT se
> CPU2TSM Support: http://www.cristie.se/cpu2tsm-supported-platforms
>
> Join us at Pulse 2012: http://www.ibm.com/pulse
>
> ________________________________________
> Från: Ehresman,David E. [deehre01 AT LOUISVILLE DOT EDU]
> Skickat: den 22 februari 2012 14:20
> Till: ADSM-L AT VM.MARIST DOT EDU
> Ämne: What if
>
> What if there were a
>
> 1)      storage pool with retonly=15 and retextra=15
>
> 2)      it received data from a backup node (NDMP) process
>
> 3)      the NDMP runs a full backup once every six months
>
> 4)      the NDMP run an incremental monthly on the months a full is not
run
>
> What data does TSM actually retain?
>
> David
>