From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Marc L. de Bruin" Subject: Can't get drives containing spare devices to spindown Date: Thu, 11 May 2006 21:51:28 +0200 Message-ID: <446395C0.5060502@debruin.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Lo, Situation: /dev/md0, type raid1, containing 2 active devices (/dev/hda1 and /dev/hdc1) and 2 spare devices (/dev/hde1 and /dev/hdg1). Those two spare 'partitions' are the only partitions on those disks and therefore I'd like to spin down those disks using hdparm for obvious reasons (noise, heat). Specifically, 'hdparm -S ' sets the standby (spindown) timeout for a drive; the 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. However, it turns out that md actually sort-of prevents those spare disks to spindown. I can get them off for about 3 to 4 seconds, after which they immediately spin up again. Removing the spare devices from /dev/md0 (mdadm /dev/md0 --remove /dev/hd[eg]1) actually solves this, but I have no intention actually removing those devices. How can I make sure that I'm actually able to spin down those two spare drives? Thanks, Marc.