If you suspect your hardware, you should verify it with an
appropriate low-level tool, like a bootable utilities image from your
drive manufacturer or similar (or memtest for memory, or etc, - using
a low-level diagnostic on hardware can really speed up and focus
software troubleshooting).
Given working hardware, according to the support in Plan 9 for your
IDE or SATA controller, do you have DMA on when it shouldn't be? I
saw i/o errors from venti when trying to force dma on a not-quite-
supported via controller we have. If 'new' is a fresh install from a
recent iso, you might want to ensure 'old' has been pull'd to the
latest venti and rd/wrarena code, or invoke wrarena on 'new' itself.
Lastly, does the venti on 'new' work for a basic operation, like vac(1)?
This month I have tested the procedure you're trying 4 or 5 times,
and so if it is encouraging, the basic software and process works as
expected/documented in venti-backup(8). I notice the lack of a bloom
filter in your venti conf; I am not implying this is the direct
source of your problem, but you should check out the latest venti(8)
and its see also's. The bloom filter is probably most critical to
performance, from what has been reported here and what I've seen, in
a new initialization scenario, so you'll probably want one.
Since your