I am having issues where an external USB3 drive(#1) is not showing up after reboot. It also doesnt not show up when holding option during boot. This external drive is a clone made with Carbon Copy Cloner. I have cloned the recovery partition as well using CCC. The external disk is not ecrypted, but the Macbook I am doing this from is with Filevault2. It shows up properly when connected as long as I don't restart the OS. If the OS is restarted, the drive will not show up in Finder, Disk Utility, System Information, or Terminal. But when I disconnect the drive and connect it again it shows up and mounts.
I fixed drive #2 issue by deleting my Time Machine backup from the Time Machine System Preferences and as soon as I connected it, showed up and asked for password. Well now I know nothing is wrong with my USB3, but still would like to know why I can't boot drive #1.
My other issue is another external USB3 drive(#2) from the same company, but more expensive model. This is my Time Machine backup. It is encrypted using the Time Machine GUI in system preferences. It doesn't ask for my password when plugged in. I have used it many times before. This drive will not show up in Finder, Disk Utility, System Information or Terminal when plugged in. Obviously it needs my password to decrypt the volume, but why isn't it asking me? The drive has sufficient power.
Obviously there is something going on with my Mac. Please help and let me know if you need more information. Also both of these external enclosures have worked great with this Macbook and my previous Macbook. Never had an issue. Macsales is not known for low quality or poorly designed products IMO.
Best Answer
So far, it seems that my MacBook doesn't recognize USB3 before login. If I plug either my Time Machine or clone which are both USB3 into a USB2 hub, both are recognized at boot using either option or command+r. You could also use a regular USB2 cable to force to USB2. This is not unusual as my Windows desktop I built is the same because the BIOS doesn't support USB3 yet. The USB3 functionality is implemented through a separate chip from the Processor or Chipset. I wonder if this is the same for MacBooks....