On Fri, Apr 15, 2005 at 08:07:10AM -0700, Kathryn Hemness wrote:
> I am in the process of setting up a 2TB disk "staging" storage unit.
> Because Solaris has a 1TB filesystem limit for I had to set up
> 3 partitions which I then defined as individual storage units in
> a storage unit group.  I have tried both the disk-staged storage
> unit and the disk storage unit using locally written scripts.

If you're using Veritas File system, then check
http://seer.support.veritas.com/docs/248416.htm
For UFS, check http://docs.sun.com/app/docs/doc/817-3801/6mjcck32j?a=view 
Solaris 9 added suppport for muliterabyte file UFS volumes.

> What happens is that when the initial storage unit gets full,
> the currently active backups using the unit fail with a media write
> error and will not continue onto the other available disk storage
> units.

You need to schedule your jobs to write to tape more frequently.
> 
> With the disk-staged storage units, the staging from disk to tape
> was immediate, but the expiration and removal of the disk image was
> not, and this behavior is not configurable (I have no idea how
> NetBackup determine that the storage unit is full to let the
> expiration and removal commence).

The images stay on disk for as long as possible and this is actually
what you want so that restores are quicker.  NetBackup is quite happy to
have images on both disk and tape and will restore from the right place.
However, you need to ensure that the images have made it to tape so that
the images can be deleted from disk when needed.

> Needless to say, I'm disappointed that Veritas released such inflexible
> storage unit options without any mention of the known limitations.
> Right now, I'm finding disk storage units to be an administrative
> nightmare.

The whole DSSU stuff is fairly new and I've heard that there will be
significant changes for NBU 6.0.  It's better than nothing right now and
as long as we understand the limitations, we can work with it.  It's
prefererable to not having them at all (which is your option too, btw).

> I do have to say that disk storage units would have been much less of
> a nightmare if I were not limited to a 1TB filesystem size (a
> restriction which will be removed in Solaris 10) and if the storage
> array were large enough to hold more than 1 days' worth of backups
> (a limitation caused my a very small budget).

As I mentioned above, an upgrade to Solaris 9 will be enough. 

-- 
Ed Wilts, Mounds View, MN, USA
mailto:ewilts AT ewilts DOT org