The client does not use the archive bit for backup, but it can reset the
archive bit after backing up the file (see the RESETARCHIVEATTRIBUTE
option).

The client manual describes by what criteria TSM's progressive incremental
backup methodology considers a file changed. See chapter 4, section "Full
and partial incremental backup".

Other methodologies include journal-based backup and incremental-by-date
(the latter being something to use more as a last resort, and should be
accompanied by periodic progressive incremental backups).

Regards,

Andy

Andy Raibeck
IBM Software Group
Tivoli Storage Manager Client Product Development
Level 3 Team Lead
Internal Notes e-mail: Andrew Raibeck/Tucson/IBM@IBMUS
Internet e-mail: storman AT us.ibm DOT com

IBM Tivoli Storage Manager support web page:
http://www.ibm.com/software/sysmgmt/products/support/IBMTivoliStorageManager.html

The only dumb question is the one that goes unasked.
The command line is your friend.
"Good enough" is the enemy of excellence.

"ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU> wrote on 2008-03-14
08:19:59:

> It CAN use the archive bit if its configured to (at least one of the
> clients I installed recently had that option in a 5.3.5 client), but
> most folks do not turn that on.  I'm talking a Windows client that is.
>
> Now, exactly how it determines a file has changed, I'm not exactly sure
> about but I think it uses a combination of size, date modified time
> stamp, and something like a CRC check.  I just can't remember all of it
> right now.
>
> See Ya'
> Howard
>
> > -----Original Message-----
> > From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf
> > Of Joni Moyer
> > Sent: Friday, March 14, 2008 9:45 AM
> > To: ADSM-L AT VM.MARIST DOT EDU
> > Subject: [ADSM-L] Archive bit: Differential Backups
> >
> > Hello Everyone,
> >
> > I have a TSM 5.3.5.2 server running on AIX 5.3 and I am doing NAS NDMP
> > backups.  I have 1 file system that appears to be doing a full backup
> > when
> > a differential backup is envoked.  Can anyone tell me how TSM
> > determines
> > if a file has been updated/created?  I'm pretty sure it does NOT use
> > the
> > archive bit, but I just wanted to be sure.
> >
> > Thanks in advance!!!!!
> >
> > ********************************
> > Joni Moyer
> > Highmark
> > Storage Systems, Storage Mngt Analyst III
> > Phone Number: (717)302-9966
> > Fax: (717) 302-9826
> > joni.moyer AT highmark DOT com
> > ********************************