Zvi Bar-Deroma wrote:
>
> I am just starting with ADSM and have to plan its database. From the little
> I already know I understand the database is very crucial in ADSM's operation
> and care must be taken to protect it. From the FAQ (in ADSTAR's site) I
> understood that ADSM can backup its database (although intuitively this
> seems far from being trivial), and that it can implement mirroring by
> itself (unrelated to the OS'es, AIX in my case, mirroring).
>
> Am I (more or less) correct with the above ?
>
> Nonetheless, I don't feel confident in having ADSM backup its own db, and
> my idea was to have its db reside on the rootvg, which will be a 4.3 GB
> disk with mirroring (2 copies). That way, occasional mksysb (or sysback)
> backups should leave me on a quiet secure track. I am not sure of the db size,
> but please read about in later. Does that sound like a reasonable strategy,
> at least to begin with ?
>
> As for db size, any rule of thumb for calculating its size ? For the first
> year, I think I'll have about 20-30 GB of disk to backup, with <= 20 clients
> and between 200,000 and 300,000 files (total). On the average I'd like to have
> 3 copies of each file. Can anyone give me a fair assumption of the required db
> size ? I guess that's it's (mainly) a function of the # of files and # of
> copies of each file.
>
> TIA,
> /Zvika
>
> Zvika Bar-Deroma
> Systems and Network manager                       Phone: (+972)-4-829-2706
> Faculty of Aerospace Engineering,                 Fax  : (+972)-4-823-1848
> Technion                                          Home phone:
> Haifa 32000                                              (+972)-4-823-5562
> Israel
>
> Internet      :   zvika AT aeserv.technion.ac DOT il
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Unless you don't have a copy of the administrator's guide, these
questions can be easily answered by reading if nothing the chapter on
recovering data.  I would strongly recommend that you use ADSM
mirroring versus the Unix mirroring because ADSM will know the names
of the mirrored file and recovery can be performed by following the book
on a step by step basis.  Thus it is best perform mirroring using files
that ADSM knows about. As far as db space is concerned and I am quoting
from the book 'the initial amount of space should be between 1 to 5%"

What is best for you depends on you.  I backup my database to a different
physical disk than the main data base mainly because I don't want to
have to manually pull out my backup tape out of the robotic system
that I use.  If you don't have a robot and you can easily take the tapes
out or are heavily reliant on your operators then backing up to tape
will work.  The problem with my scenario is that if I lose my scsi
channel or disk controller I have lost my ADSM data base but then again
I would also have lost all my other data files as well.