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 Disinformation Analyst _______________________________________________ Linux-PowerEdge mailing list [email protected] https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
