Mount 2 USB drives at boot & power saving.

[rookie65]

I have followed this guide
http://elinux.org/R-Pi_NAS
I have used 2 identical 2 T USB drives. They are in powered enclosures.
I did this sudo mkdir /home/shares/public/disk1, followed by sudo mkdir /home/shares/public/disk2
then sudo mount /dev/sda1 /home/shares/public/disk1, followed by sudo mount /dev/sdb1 /home/shares/public/disk2
This works fine but sometimes after a reboot, disk 1 will be mounted here /home/shares/public/disk2 and vice versa
How do I force them to mount in the correct place?

Also how do I get them to power/spin down to save power/wear when they are not being accessed?
Thanks

[Aydan]

Mount via UUID in fstab

Regards
Aydan

[mutley]

Above answered the mount problem.

look at hdparm and smartctl to control the spindown, but most USB controllers do not support these commands / will not pass them to the native IDE / ATA / SATA disk. So even if the disk itself does support the functionality you may not be able to pass it the command.