I copy the data arenas to another machine and when they are full (500mb per arena) I burn them to cd.

I us this script to copy the arenas

http://plan9.bell-labs.com/sources/contrib/maht/rc/vbackup

It's slightly sloppy in that I could just append the unwritten bytes but for < 500mb who cares, its a 1gbe after all.

Venti dumps give me a full history of file changes. On the plan9 central server one can browse the daily snapshots for 10+ years of plan9 development. It also coalesces duplicate blocks so storing 20 copies takes as much room as one.

Venti is available for plan9 and Lunix.

i accidentally wiped $home this week, then :

    cp `{yesterday $home}/* $home

got it all back