Subfile backup on this big a filesystem would probably be... interesting
to restore :)

Theres also a 2GB file limit for subfile and with 15TB data I'm guessing
that there might be a few files bigger than that.

And on Windows I believe that atleast permissions arent restored correctly
when using subfile but that is/was? a deficiency in NTFS.

But apart from that I guess only the ACL would be backed up...

-km

On 16/02, Len Boyle wrote:
> What happens if you are using subfilebackup. Will it just backup the acl's as 
> the data blocks have not changed?
> 
> len
> 
> -----Original Message-----
> From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf 
> Of km
> Sent: Monday, February 16, 2009 4:26 PM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: Re: [ADSM-L] Backup of ownership and ACLs
> 
> If all the ACLs are updated daily I guess thats not a problem, just
> update them again after the restore :)
> 
> Or make a script that saves the ACLs before backup to a file and run as
> a preschedulecmd.
> 
> Sounds like it could be worth it to avoid unnecessarily backing up 15 TB of
> data every day.
> 
> -km
> 
> On 16/02, Mark Stapleton wrote:
> > Perhaps. But what happens when you restore files without the latest ACLs? 
> > They're set for a reason, and to not restore the entire file's contents 
> > strikes me as rather worthless.
> > 
> > --
> > Mark Stapleton
> > System engineer, CDW
> > 
> > 
> > -----Original Message-----
> > From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On 
> > Behalf Of Rolf Meyer
> > Sent: Monday, February 16, 2009 3:16 PM
> > To: ADSM-L AT VM.MARIST DOT EDU
> > Subject: Re: [ADSM-L] Backup of ownership and ACLs
> > 
> > Hello
> > 
> > I think, there's an option called SKIPACLUPDATCHECK, which can be used
> > to prevent incr backups just because of changing ACL-infos.
> > 
> > Give it a try.
> > 
> > Rolf Meyer
> > Storage Consultant
> > PROFI Engineering Systems AGAlexander Födisch schrieb:
> > > Hi all,
> > >
> > > if we change the ownership (chmod/chgrp) or the ACLs of files/folders on
> > > our GPFS-filesystem, all affected
> > > data will be backed up again from TSM because the ctime was changed -
> > > same behaviour on a XFS filesystem.
> > > We often have to change recursively the ACLs of a 15TB-folder and so
> > > this 15TB are backup up nearly daily...
> > > I understand the necessity of backing up metadata as ownership or ACLs
> > > :) But is there an other possibility?
> > >
> > > Can we backup just the metadata of changed files instead of all the
> > > data? Depends this on the filesystem?
> > 
> > 
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> > 6:09 PM