On 2015-11-01 09:33, Ken Long wrote:
> I get a similar read-only status when I try to remove the drive from the array..
> 
> Too bad the utility's function can not be slowed down.. to avoid
> triggering this error... ?
> 
Actually, there are a couple of ways you could do this.  The most reliable way to do it
(and arguably the only correct way) is to use the blkio cgroup to put bandwidth  or
IOPS limits on the process.  For authoritative info about how to do this, check
Documentation/cgroups/blkio-controller.txt in the Linux source tree.

If the issue really is the device not responding soon enough, you may also try increasing
the device timeout the kernel uses.  A udev rule like the following will increase the
timeout for all ATA/SCSI/USB (it says SCSI devices, but all ATA and USB devices get
routed through the SCSI subsystem anyway unless you're using really old and deprecated
drivers) devices to 150 seconds (2.5 minutes, which is reasonable for most non-enterprise
devices):

DRIVER=="sd", SUBSYSTEM=="scsi", ENV{DEVTYPE}=="scsi_device", ATTR{timeout}="150"