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
> ********************************