Postgres backend to backup system

Hello,
I don't know if this is the forum for this but here goes.

I am interested in using Postgres as the backend to a backup system.
Does anyone have any experiences or ideas on this? I have a project in
mind to develop a web based backup system using PHP that stores backup
information in Postgres. This is the typical types of information that I
feel need to be stored in postgres:

Tape ID
Location of tape in autoloader magazine
Directory file sizes
Total Archives on tape
Total bytes in archive
Archive location of a file or directory on a tape
Total bytes on tape
Date archive was written to tape
Server associated with an archive
Absolute path to file or directory on tape

My log files are generated by using the "v" option of the "tar" command.
These create daily log files that are 6-8 mb that list every file that
is backed up. This comes out to 75,000 lines per day. If you had an
autoloader that you cycled through with 10 tapes for example, that could
contain 750,000 entries.

My system backups up anything that can run rsync. For me right now that
is Linux servers, Novell servers, MAC running OSX, and Windows servers
running rsync. Because there are many types of servers the database
should be able to store which server, archive number a file or directory
is in.

If you were to search in the database for a file or directory, it would
return a list that gave you the tape(s), date(s), archive(s) number on
tape, etc.

Any suggestions would be appreciated.

--
Kent L. Nasveschuk <kent(at)wareham(dot)k12(dot)ma(dot)us>