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Is it possible to gain access to USB External Hard Disk to check health of External USB Hard Disk Connected to Host (macOS Sierra 10.12.6) from the Guest CentOS 7 Linux?

Check the health of the USB HD how? fsck? What's the file system of the HD?
Eject the HD from your OSX and use the Devices » USB menu to give it access to the VM. That's the fastest and easiest way. For more complicated setups, please read the following thread: USB basics and troubleshooting.

Thank you for your answer!