I have a 750GB Western Digital external HDD which I use for Time Machine backups (MBP, OS 10.10.3). Today I had the need to boot to recovery, which I did from said backup. But I was unsuccessful in doing it again, whenever I booted with ⌘-R, OSX went straight to internet recovery. I can still boot to recovery from it by holding ⌥ at boot and choosing the disk.
Now, when booting from my internal disk and running a
Verify Disk on the backup drive, it says
Error: This disk doesn’t contain an EFI system partition. If you want to start up your computer with this disk or include it in a RAID set, back up your data and partition this disk.
diskutil list reveals
/dev/disk3 #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *750.1 GB disk3 1: Microsoft Reserved 134.2 MB disk3s1 2: EFI EFI 209.7 MB disk3s2 3: Apple_HFS WD 749.6 GB disk3s3
I never bothered to check it before, so I do not know if something has changed there, but firstly, I do not know where the
Microsoft Reserved partition comes from, or what it is, secondly, I can see the EFI partition, so why does Disk Utility ignore it? And how do I make it useable for recovery without erasing all data?