Terminal command to find hd bay name?
system_profiler SPSerialATADataType


Located at /usr/sbin/system_profiler. For example:

SATA/SATA Express:

    Intel 7 Series Chipset:

      Vendor: Intel
      Product: 7 Series Chipset
      Link Speed: 6 Gigabit
      Negotiated Link Speed: 3 Gigabit
      Physical Interconnect: SATA
      Description: AHCI Version 1.30 Supported

        APPLE HDD ST1000LM024:

          Capacity: 1 TB (1,000,204,886,016 bytes)
          Model: APPLE HDD ST1000LM024
          Revision: 2AR20008
          Serial Number: XXXXXXXXXXXXXX
          Native Command Queuing: Yes
          Queue Depth: 32
          Removable Media: No
          Detachable Drive: No
          BSD Name: disk0
          Rotational Rate: 5400
          Medium Type: Rotational
          Partition Map Type: GPT (GUID Partition Table)
          S.M.A.R.T. status: Verified
          Volumes:
            EFI:
              Capacity: 209.7 MB (209,715,200 bytes)
              File System: MS-DOS FAT32
              BSD Name: disk0s1
              Content: EFI
              Volume UUID: 0E239BC6-F960-3107-89CF-1C97F78BB46B
            iMac HDD:
              Capacity: 999.35 GB (999,345,127,424 bytes)
              Available: 241.23 GB (241,225,633,792 bytes)
              Writable: Yes
              File System: Journaled HFS+
              BSD Name: disk0s2
              Mount Point: /Volumes/iMac HDD
              Content: Apple_HFS
              Volume UUID: ECE5EA87-55BF-33A8-AA27-FB7BE9F48CC4
            Recovery HD:
              Capacity: 650 MB (650,002,432 bytes)
              File System: Journaled HFS+
              BSD Name: disk0s3
              Content: Apple_Boot
              Volume UUID: A6D16761-A44A-3B42-9C8D-DDDD4E42B6F6

    Intel 7 Series Chipset:

      Vendor: Intel
      Product: 7 Series Chipset
      Link Speed: 6 Gigabit
      Description: AHCI Version 1.30 Supported