Which disk controllers work best with Linux?
kris at catonic.us
Tue Sep 14 06:39:06 CDT 2010
On Tue, 14 Sep 2010, Robin Bowes wrote:
> > The only time we use hardware RAID is if the workload really needs
> > the low-latency writes offered by battery-backed write caching.
> If you don't want to use HW raid, but want battery-backed write
> caching, you can use a HW controller with a battery-backed cache (PERC
> 6/i, H700, etc) and configure each drive as a separate RAID0 volume.
DBAN positively does not like logical drives configured for Caching IO
and WriteBack on SCSI PERC 4s. Attempting to wipe multiple drives on a
single controller (or dual-port controller) will result in SCSI errors
which are fatal to the program. They do not appear to wedge the Linux
kernel; it merely bides it's time until the controller / IO has
completed and returned. DBAN falls apart because of device and
unhandled errors, as DBAN is working directly with the device nodes in
/dev and not using the drives under any form of filesystem.
Kris Kirby, KE4AHR
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