Spin Down Idle Hard Disks

My home server uses mdadm software RAID for my media share. The array is made up of ten disks, so it only seemed natural to spin them down to save power when our family wasn’t home. Powering them off when they aren’t in use should also reduce the case temperature, hopefully increasing the lifetime of the hard disks.

mdadm auto-read-only

If you’ve used mdadm for a while, you may have come across a situation where your array’s status says auto-read-only. If you see this, there’s a very easy way to fix it.