I suspect it backs up used blocks based on what VMWare knows, not the guest OS.

Andy Huebner


-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
Michael Roesch
Sent: Wednesday, July 10, 2013 3:00 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: [ADSM-L] FW: [ADSM-L] Should CBT be enabled before using TSM for 
VE to save space?

So this sounds like a draw to me ;-)


On Tue, Jul 9, 2013 at 4:49 PM, Stefan Folkerts
<stefan.folkerts AT gmail DOT com>wrote:

> I don't think this is correct, TSM for Virtual Environments (and even 
> just the BA client with a simple full backup) will only backup the 
> blocks that are in use inside the .vmdk file, this information is 
> provided by the vSphere storage API.
>
>
> On Tue, Jul 9, 2013 at 3:15 AM, Stackwick, Stephen < 
> Stephen.Stackwick AT icfi DOT com> wrote:
>
> > According to this:
> >
> >
> >
> http://www-01.ibm.com/support/docview.wss?uid=swg21641914&myns=swgtiv&;
> mynp=OCSS8TDQ&mync=E
> >
> > TSM4VE backs up the whole disk. And that's been my experience.
> >
> > Steve
> >
> > STEPHEN STACKWICK | Senior Consultant | 301.518.6352 (m) | 
> > Stephen.Stackwick AT icfi DOT com | icfi.com ICF INTERNATIONAL | 410 E. 
> > Pratt Street Suite 2214, Baltimore, MD 21202 |
> > 410.539.1135 (o)
> >
> > > -----Original Message-----
> > > From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On 
> > > Behalf Of Robert Ouzen
> > > Sent: Monday, July 08, 2013 8:58 AM
> > > To: ADSM-L AT VM.MARIST DOT EDU
> > > Subject: [ADSM-L] FW: [ADSM-L] Should CBT be enabled before using 
> > > TSM
> for
> > > VE to save space?
> > >
> > > Hi Wanda
> > >
> > > No quite sure at least in Vsphere 5 (maybe Vsphere 5.1) , I always
> check
> >  with the
> > > command: dsmc show VM all  and the parameter :  changeTracking: 
> > > Off
> > >
> > > About the first backup will take only the USED space , at least in 
> > > my
> > environment
> > > some machines works fine  but some others backup the ALL space !!!
> > >
> > > Best Regards
> > >
> > > Robert
> > >
> > > -----Original Message-----
> > > From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On 
> > > Behalf Of Prather, Wanda
> > > Sent: Monday, July 08, 2013 3:47 PM
> > > To: ADSM-L AT VM.MARIST DOT EDU
> > > Subject: Re: [ADSM-L] Should CBT be enabled before using TSM for 
> > > VE to
> > save
> > > space?
> > >
> > > If your VM's were created in VSphere 5, CBT will be on by default.
> > >
> > > My understanding is that either way (starting with CBT on or off), 
> > > you
> > should
> > > only get USED space on the first backup.
> > >
> > >
> > > -----Original Message-----
> > > From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On 
> > > Behalf Of Michael Roesch
> > > Sent: Monday, July 08, 2013 4:29 AM
> > > To: ADSM-L AT VM.MARIST DOT EDU
> > > Subject: [ADSM-L] Should CBT be enabled before using TSM for VE to 
> > > save space?
> > >
> > > Hi there,
> > >
> > > I've read here
> http://www-01.ibm.com/support/docview.wss?uid=swg21608413
> > > that TSM for VE is using "content-aware" backup, if CBT is 
> > > enabled. It
> > also says
> > > that TSM for VE will enable CBT after the first backup.
> > >
> > > So I'm wondering if enabling CBT before performing the first 
> > > backup
> would
> > > make TSM for VE backup only the used blocks (i.e. used space) and 
> > > hence
> > would
> > > save space on the storage pool?
> > >
> > > Or would TSM for VE still backup the full VMDK, including possible 
> > > lots
> > of unused
> > > space inside it on the first backup?
> > >
> > > Regards,
> > > Michael
> >
>