What are you all doing for Disk-to-disk backups?

I'm getting a chance to redesign some infrastructure and Disk-to-disk might
play an expanding role.

Currently we keep about 5TB on disk as a primary backup media, simply
writing to a large NFS chunk.  We stage another TB or so to disk now but
only until it's later duplicated to tape.  We use no formal DSSU - it's all
vault jobs & custom scripts.

Netapp presented their VTL to me.  It's pretty good but I'm also interested
in possible automated D2D offsites.

What I want is a block-oriented duplication to a remote device, 1000 miles
away - OC1 link.  It's not practical to duplicate every tape block to a
remote library at this speed, I need more of a changed-block oriented
duplication for the remote disk unit.

Netbackup would still be the software layer.  I'd like an appliance head or
just software solution I can hang in front of anybody's disks.  

Data Domain makes the right kind of software, they just tie it too tightly
to an appliance, IMO, rather than letting me hang my own disks on the
backside.

I'm backing up 20TB a week now.

-M

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  Mark Donaldson - Systems Administrator - 303-664-2040
  Corporate Express - Broomfield, Colorado
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