Hi Jon, thanks for the reply!

Jon LaBadie wrote:

My main concern is that we have to be "up" round the clock these days as we have people connecting during their work day, 9 hours different from ours. So having major services disrupted in the middle of the night for backups doesn't seem a viable solution anymore, as it hits the other people in the middle of the day.

"Up" is less a concern to me than "connected".  Are some of these
people working on laptops or other computers that are not accessible
to your backup server except at certain times?

If you are willing to use tar as as your backup program (many, many
amanda sites do that) then there is not problem.  You say you have
basically 400GB of data.  The basic unit of backup for amanda is
called a "DiskList Entry" (DLE) after the name of a config file.
With tar as the backup program you can specify directory tree's
as a DLE rather than filesystems.  So you could have a DLE for
/boot, /var, /home, /usr/local, /usr (without local), /opt,
/database, and one for / without all the others.  This is done
by "including" or "excluding" files and directories in the DLE
config.  Now with 16 DLE's from two systems (or even more is you
wish), amanda can spread the level 0's of those 16 items over
your dumpcycle (typically a week).  So on a typical day, only
2 or 3 of the DLEs will get a level 0 and on average your daily
backups will be 1/7th of your 400GB or about 60GB/day.

Thanks again,

Don