5 Nov
2010
5 Nov
'10
11:06 a.m.
On 5 Nov 2010 at 13:52, Dave McGuire wrote:
There is no strange formatting, in the way that we
normally think of
"formatting". It is not possible to reach those levels of a SCSI
device, so there are no incompatibilities. The host says "give me
block number 5324985", and sometime later, the target hard drive says
"hey host, here's the data for block number 5324985 that you asked
for". Zero format compatibility issues.
It depends a lot on the manufacturer and device, as with all things.
There were some manufacturers who did all manner of bizarre things,
for example, with Mode Select commands. While you'd love to think
that there's a standard set of commands that everyone interprets in
the same manner, it's simply not true in the real world.
As regards tape drives, I found quite a variation in what was
supported and not. Read-after-write capabilities varied all over the
place. Some prohibit it entirely; others say that resuming reading
after a filemark is legitimate and so on.
Old devices may support only the short command forms; some devices
may not support the entire long command set...
It's pretty much like anything else.
--Chuck