[miod]

Linux reports...

[sda] Read Capacity (1) failed: Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[sad] Sense Key : Not Ready [current]
[sda] Add. Sense: Logical unit not ready, cause not reportable

Is this an issue with my setup, or does this look like the drive has failed?

In order to properly identify an SCSI device, the operating system must send a TUR (Test Unit Ready) command to the device. In case of a hard disk, this will cause the motor to start if it wasn't started, and report its parameters. If the operation fails (for example because the disk has not been able to spin up correctly), no parameters gets returned and the disk can not be used.

With such an old disk, it is very likely that the spindle can not reach its nominal speed fast enough. You might want to check that the power applied to the disk is correct; also you might want to gently rock the disk (while not powered on) in case something is stuck inside.