I have a 1TB Western Digital external hard drive that I use for Time Machine backups (and storage of a few other large files). Recently (since Mountain Lion, I think) I've been getting the following message when ejecting the drive:
"Time Machine Backups" is a partition on a disk that has 2 partitions. Do you want to eject "Time Machine Backups" only, or both partitions?
I haven't partitioned this drive myself, and I didn't get this message before a few months ago. According to Disk Utility, there is only one partition occupying the entire drive.
This isn't really a problem in itself (I just choose "Eject All"). However after ejecting the drive (all partitions) and waiting for it to disappear from the Finder, I still get the following message when I physically unplug it:
The disk was not ejected properly. If possible, always eject a disk before unplugging it or turning it off.
I don't want to damage my drive, so can anyone shed any light on what's going on? It's worth noting that neither of these problems seem to occur if I eject before Time Machine performs a backup.
diskutil list gives the following output:
/dev/disk0 #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *250.1 GB disk0 1: EFI 209.7 MB disk0s1 2: Apple_CoreStorage 168.3 GB disk0s2 3: Apple_Boot Recovery HD 650.0 MB disk0s3 4: Microsoft Basic Data Windows 80.9 GB disk0s4 /dev/disk1 #: TYPE NAME SIZE IDENTIFIER 0: Apple_HFS Macintosh HD *168.0 GB disk1 /dev/disk3 #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *1.0 TB disk3 1: EFI 209.7 MB disk3s1 2: Apple_CoreStorage 999.9 GB disk3s2 3: Apple_Boot Boot OS X 134.2 MB disk3s3 /dev/disk5 #: TYPE NAME SIZE IDENTIFIER 0: Apple_HFSX Time Machine Backups *999.5 GB disk5