Re: [Bacula-users] TSM-style perpetual-full?

[Mike E. <mik...@ma...>]

On Mon, 29 Oct 2007, Michael Lewinger might have said:

> Hi Mike,
> 
> It looks all things are covered in Bacula: retention times, incremental
> backup. But then I'm not a TSM expert.
> 
> Michael
> 
> On 10/29/07, Mike Eggleston <mik...@ma...> wrote:
> >
> > I like bacula and what it does for me (thank you development team).
> > One issue I have is not really bacula, the issue is the long time
> > required to write backups to tape. Is there anything in bacula like
> > TSM's perpetual full where I can see the most current files from the
> > client in the 'restore' command, files removed the client are kept
> > for a specific number of days, and only the files that have changed
> > during the night are written to backup tape ad infinitium?

The big difference I can see is the perpetual full. Bacula will upgrade
a backup level to Full if no other Full is found for the client. TSM
will backup any files you tell it to regardless of backup level, and
TSM will keep the file for a certain amount of time (30 days, etc) after
the file is deleted from the client. TSM also knows what the most current
files for a client are, so like 'restore' in bacula you can choose which
files to load back to the client. You do not have to select a file by
job id. You can ask for a list of 'active' and 'inactive' versions of a
given file or wild card and like bacula's 'restore' you can choose which
files to load back.

The biggest difference for what I'm wanting between bacula and TSM is
the 'perpetual full'. Just backup the files from the client and let me
choose which files by date to restore (bacula does the latter).

I greatly agreed with the idea of Full/Differential/Incremental backups
(levels 0/1/2 from BSD) until I started with TSM. The TSM method, once
you understand what it is doing, works very well. I was very skeptical
at first of TSM until I had used it a while. The idea is similar to CVS
or RCS. Only the files that have been modified get new version numbers.

Does that make sense or am I rambling?

Mike