hdparm und sdparm
sind beides sehr mächtige tools, hier schonmal was nützliches:
Additionally you can shorten the time after which the drive spins down using sdparm in the following way:
sdparm –set=SCT=3600 /dev/sda
This will set the time till spin down (SCT = Standby ConditionTimer) to 6 minutes (= 3600 tenth of a second).
hdparm -y /dev/sdb1
direkt in standby schicken