The new unraid 6 has a very good documentation.  With videos to show it as well.  However, it doesn't show the same instructions given by users before, such as using a pre-clearing script to prepare the drives.  Is this still the best way? Or should I just assign new drives unraid, and let it format each drive on it's own?  Does unraid format do it simultaneously?

Preclear is the best way to proceed unless you don't mind having your array be unusable for the hours at a time it will take for it to clear your new drive.

Thanks BRiT.  After pre-clear, will you know if drives have defect?  From the generated reports?

Pre-clearing only saves time if you're adding the drive to an existing UnRAID array with parity protection.

 

If you're creating a new configuration, UnRAID does NOT clear the drives ... it just formats them (a very quick process) and they're then ready for use.

 

However, the pre-clear script is also used by many to test new drives for any infant mortality issues/defects ... i.e. SMART parameters that change for the worse; sectors that are reallocated; etc.    It's a good tool for this; but you can also do this with the manufacturer's diagnostics, which may be more convenient, depending on what computer resources you have available to do the testing.

 

If you use the pre-clear script, then you look at the report that is generated, which will show you what SMART parameters changed, and specifically whether or not there are any reallocated sectors on the drive.

 

Regardless of WHAT utility you use to test your drives, it's a good idea to test them before putting them in service.

 

 

To make life easier.... I now use the Pre-clear plugin.... it makes it soooo simple. Just read the installation instructions carefully.

 

https://lime-technology.com/forum/index.php?topic=39985.0