Hi, I recently got a Drobo with 4X1TB WD Green harddrives. It is connected to the mac with firewirw 800. The Drobo works quite good except for one thing; it keeps my iMac (i7 2010) from going to sleep automatically. With all other usb / firewire HD´s my iMac sleeps fine.
I did find a temporary solution to the problem; by changing the order of the disks the Drobo and iMac sleeps like a child when they are supposed to
But as soon as I turn my iMac off (and leave it off for a day or so) the problem comes back; while starting the iMac the Drobo flashes red and reboots itself - after this it seems ok but again keeps my iMac from sleeping.
I can then rearrange the disk set and the story goes on…
I have filed a support ticket #110127-000013