Not sure if hdparm -s0 /dev/sdX is the right command here:
From the hdpam man page (see below) the capitalized S should be it.
However, for me (on the 859) it does not work. I want it to spin endlessly, because otherwise the drives will die in no time (as it is, even with the 1hour standby setting the clock up more than one load cycle per hour (!) as seen in the SMART settings). Also there is the annoying 10s lag as the disks spin up.
The configuration interface settings with regard to standby only effect the last four drives (of my eight). The others will go into standby after the time set in the config interface (although standby is turned off). This must be a bug.
Does anyone know how the standby is internally managed. It does not seem to be user settable using hdparm. Maybe a cron process will re-set it regularly to whatever the config interface thinks should be right. I filed a bug report, but nobody replied.
-s Enable/disable the power-on in standby feature, if supported by the drive. VERY DANGEROUS. Do not use unless you are absolutely certain that both the system BIOS
(or firmware) and the operating system kernel (Linux >= 2.6.22) support probing for drives that use this feature. When enabled, the drive is powered-up in the
standby mode to allow the controller to sequence the spin-up of devices, reducing the instantaneous current draw burden when many drives share a power supply. Pri-
marily for use in large RAID setups. This feature is usually disabled and the drive is powered-up in the active mode (see -C above). Note that a drive may also
allow enabling this feature by a jumper. Some SATA drives support the control of this feature by pin 11 of the SATA power connector. In these cases, this command
may be unsupported or may have no effect.
-S Put the drive into idle (low-power) mode, and also set the standby (spindown) timeout for the drive. This timeout value is used by the drive to determine how long
to wait (with no disk activity) before turning off the spindle motor to save power. Under such circumstances, the drive may take as long as 30 seconds to respond
to a subsequent disk access, though most drives are much quicker. The encoding of the timeout value is somewhat peculiar. A value of zero means "timeouts are dis-
abled": the device will not automatically enter standby mode. Values from 1 to 240 specify multiples of 5 seconds, yielding timeouts from 5 seconds to 20 minutes.
Values from 241 to 251 specify from 1 to 11 units of 30 minutes, yielding timeouts from 30 minutes to 5.5 hours. A value of 252 signifies a timeout of 21 minutes.
A value of 253 sets a vendor-defined timeout period between 8 and 12 hours, and the value 254 is reserved. 255 is interpreted as 21 minutes plus 15 seconds. Note
that some older drives may have very different interpretations of these values.