@trismiles performing the PRAM and SMC reset instructions provided by Apple support page, these also reset the ports on the mac.
@trismiles again, the major change is the OS, if something is wrong with the OS upgrade, external devices might not be detected correctly
@trismiles we recommend testing the drive on another mac to make sure the drive is still working correctly correctly
@trismiles After an OS upgrade, the I/O drives might not load correctly and you need to reset the ports to reload drivers