Hi,
I've got a question about how NetWorker processes incrementals.
I backed up a new folder, D:\Stuff, so an inital full save set was made of
20,000 files taking up 5 GB.
I then created a new subfolder, D:\Stuff\Temp, and I moved ALL files from
D:\Stuff into D:\Stuff\Temp. So, I now have D:\Stuff\Temp which contains
all the files, and D:\Stuff which has no files, but just the subfolder Temp
in it. I then started an incremental backup.
Final result: *nothing* was backed up.
So what is the process for the incr ? Is it :
1. NetWorker indexes all the files in the location to be incrementally
backed up ?
2. then, it creates CRC's and cross-references that to the index of the
original full ?
3. then, only files that do not have a match in the existing full index
from step 2 ?
BUT, and this is sorta important, if I go to NetWorker User, and look at
available files from that incr backup, NOTHING is there. This makes sense
of course, as there were no file changes incrementally backed up, but what
if you massively altered the directory structure and you lost that ?? You
would not be able to reconstruct the changed structure !
e.g. a user called Joe Tucci spends 8 hours on Wednesday reorganising his
work folder. he does not EDIT a single file, but that 8 hours of
organisation work IS work (ok, maybe Joe should've had a better
organisation system for his files before now, but still ...). Then, on
Thursday morning an incremental backup happens at 3:33 am. On Thursday
morning, a NAS box explodes wiping out the entire data center (as that was
the particular revision of Celerra that they made out of nitro-glycerine.
an easy design mistake to make. oops). But, Joe thinks "that's ok !, the
backups were made, so all my folder reorganisation is safe !" ... but
actually, Joe's out of luck, as NOTHING was saved of his reorganisation as
NetWorker decided that no files had changed so it simply backed up NOTHING
(so all the 8 hours of folder reorganisation that Joe did is lost). Joe can
get all his files back from the Wednesady morning backup, but he's going to
have to do all that 8 hours of reorganisation again by hand.
Is that right ?? I'm just quite curious, as it might be useful to backup
changed folder structures (i.e. fair enough don't backup the files as
nothings changed, but DO at least backup an index of the changed folder
structure every night). Is there some option to do this ? And also, what is
the exact process by which NetWorker determines what will and will not be
backed up ?
Thanks,
Roy.
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