I just bought two new HGST 6TB Deskstar NAS drives, for my new Synology DiskStation DS415+.

Before actually using the hard drives, I am looking for a way to diagnose the hard drives and check the health, for example check for bad sectors. I found this software:

http://hddguru.com/software/2006.01.22-HDDScan/

Is this software the right software to start with ? Also found http://www.hdtune.com/

What is the best way to check the health of those new hard drives ?

Some time passed since I saw Hdtune, but I don't think it changed much since then.

If you're looking to check your HDDs at the sector level, HDD Scan will be the better and more advanced option. Just get the latest version of it, as the one from 2006 is surely not the recent: http://hddscan.com/

Also, if you prefer more thorough testing and since the drives are new, you can additionally perform write test (called "Erase" in the software).
But this is applicable for an empty drives or the ones with unnecessary data only, as "Erase" will do what it says -- wipe the data irreversibly.

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