Hi,

I know there is backup software that allows incremental and
differential backups so that it isn't always necessary to backup
everything even if only some data were added or changed.

The problem is that in my case there is also a lot of re-structuring
going on with my data, i.e. data move from one directory to a new or a
different directory. My worries are that if I use incremental or
differential backups I will get lots of duplicate files during a
restore. Am I right?
If yes, is there anything I can do about it? Which would be the best
backup strategy or software solution for my purposes?

Regards,
Peter

[ Post a follow-up to this message ]

On 4 May 2005 07:02:48 -0700, "Peter Frank" <peter_frankde@yahoo.de>
wrote:

>Hi,
>
>I know there is backup software that allows incremental and
>differential backups so that it isn't always necessary to backup
>everything even if only some data were added or changed.
>
>The problem is that in my case there is also a lot of re-structuring
>going on with my data, i.e. data move from one directory to a new or a
>different directory. My worries are that if I use incremental or
>differential backups I will get lots of duplicate files during a
>restore. Am I right?
>If yes, is there anything I can do about it? Which would be the best
>backup strategy or software solution for my purposes?
>
>Regards,
>Peter


Good question.  I guess the first question is which OS are we talking
about?  I'm pretty sure that with Unix incremental backups check
mtime, which would definitely change if you move data.  In windows I
thought there was an archive bit or some such that only got flipped by
the backup software.

I'm sure someone who actually knows will correct me but I think which
OS you're using would be a needed piece of info.

~F

[ Post a follow-up to this message ]

"Peter Frank" <peter_frankde@yahoo.de> writes:
> The problem is that in my case there is also a lot of re-structuring
> going on with my data, i.e. data move from one directory to a new or a
> different directory. My worries are that if I use incremental or
> differential backups I will get lots of duplicate files during a
> restore. Am I right?
> If yes, is there anything I can do about it? Which would be the best
> backup strategy or software solution for my purposes?

You might design your backup system to know about the duplicates,
perhaps by tracking the files as you move them around, or else by
detecting duplicates during backup, depending on how systematic the
file motion is.  I don't know of backup programs that do it
automatically.  Whether it's worth writing some special scripts for it
depends on your installation and needs.

[ Post a follow-up to this message ]

On Wed, 04 May 2005 17:17:29 GMT, Faeandar <mr_castalot@yahoo.com>
wrote:

>On 4 May 2005 07:02:48 -0700, "Peter Frank" <peter_frankde@yahoo.de>
>wrote:
> 
>
>
>Good question.  I guess the first question is which OS are we talking
>about?  I'm pretty sure that with Unix incremental backups check
>mtime, which would definitely change if you move data.  In windows I
>thought there was an archive bit or some such that only got flipped by
>the backup software.
>
>I'm sure someone who actually knows will correct me but I think which
>OS you're using would be a needed piece of info.
>
>~F


What about something like Avamar or Data Domain?  Avamar does byte
level checksumming so they only backup a certain byte pattern once.
In the case of, say, moving excel files from one dir to another the
byte patterns don't change, just the location.  In which case the
software would do a comparison and find it already has that pattern
backed up.

I believe Data Domain is similar in concept but not sure.  Avamar,
however, is quite cool.  We use it in some places but not all.
Superstition, gorilla management, et al.

~F

[ Post a follow-up to this message ]

On 4 May 2005 07:02:48 -0700, "Peter Frank" <peter_frankde@yahoo.de>
wrote:

>Hi,
>
>I know there is backup software that allows incremental and
>differential backups so that it isn't always necessary to backup
>everything even if only some data were added or changed.
>
>The problem is that in my case there is also a lot of re-structuring
>going on with my data, i.e. data move from one directory to a new or a
>different directory. My worries are that if I use incremental or
>differential backups I will get lots of duplicate files during a
>restore. Am I right?
>If yes, is there anything I can do about it? Which would be the best
>backup strategy or software solution for my purposes?

Ideally, your backup software would backup the directory/folder files
as well as their contents.  On restores, again ideally, they would
know enough to delete files that had been moved as you go through the
different backups (i.e., full & then differential restore, or full
through all incrementals restore).

I have not had to deal with this type of issue for awhile, so it's
worth testing this prior to choosing which backup product you're going
to use.

--- jls
The preceding message was personal opinion only.
I do not speak in any authorized capacity for anyone,
and certainly not my employer.

[ Post a follow-up to this message ]

Sorry for the late reply. I'm using Windows 2000 but am thinking about
installing Linux parallel to Windows.

Peter

[ Post a follow-up to this message ]

I'll have a look at these. So far, I have used a backup software called
"Phoenix Backup Professional" but it can't properly deal with the
re-structuring as I mentioned in my original post.

Peter

[ Post a follow-up to this message ]

If this is data that will all be superceeded with new data in a year or so,
you could just back it all up as is (ugly I know) onto media which you can
expire in a year or so, or into a backup server which allows certain file
types to expire after a certain number of days.

Its an easy solution and if your system stabilized more in the next year or
so, soon all of your discombobulated data will be expired out.  Maybe it
will work for you.

John Rigler
Infrastructure Architect
Managed Security Services - IBM
jrigler@us.ibm.com

"jlsue" <jeffls-delete@sbcglobal.net> wrote in message
 news:l1bk71lm10eq3qflt9nmkh5jkqppe8el6b@
4ax.com...
> On 4 May 2005 07:02:48 -0700, "Peter Frank" <peter_frankde@yahoo.de>
> wrote:
> 
>
> Ideally, your backup software would backup the directory/folder files
> as well as their contents.  On restores, again ideally, they would
> know enough to delete files that had been moved as you go through the
> different backups (i.e., full & then differential restore, or full
> through all incrementals restore).
>
> I have not had to deal with this type of issue for awhile, so it's
> worth testing this prior to choosing which backup product you're going
> to use.
>
> --- jls
> The preceding message was personal opinion only.
> I do not speak in any authorized capacity for anyone,
> and certainly not my employer.

[ Post a follow-up to this message ]