I have an iMac9,1. I replaced the optical drive with an SSD. I have the OS installed on the SSD and the HDD is now for files. I have noticed that sometimes after booting that the SSD will be designated dev/disk0 and other times the HDD will be. I need to make sure that the HDD is always designated dev/disk0 how can I go about doing this. What exactly is causing this to change during startup?
It seems to change after I use the Option key to call the Startup Manager.