I have known for many years now that all of the gurus in this forum swear by pre-clearing new disks before adding them to the array.

 

I on the other hand have never done this - I just add or replace disks in the array and let unraid do the rest.  Never had an issue with this and frankly the unraid manual doesn't ask me to do anything other than that either. 

 

The main reason for this is that the command line scares the crap out of me, and I have also never been able to find a SIMPLE set of instructions on how to do the pre-clearing.

 

If pre-clear is so important, why has this not been added to the GUI already?  Does Limetech not support this procedure?  To me it makes sense to do it on new disks...  but again, if it's not in the GUI, I personally am not comfortable doing this right now.  The new GUI in V6 is one of the best things to ever happen to unraid so adding this feature makes logical sense...

 

Thoughts??

There's a plugin now that makes this easier to do ... but as you've noted, it's not actually required, as UnRAID will clear any new disks as needed before adding it to the array. [ http://lime-technology.com/forum/index.php?topic=39985.0 ]

 

Pre-clearing serves two useful functions:

 

(1)  It eliminates the array "down time" that you'll have during the clearing process; and

 

(2)  it does a nice test of the drive to ensure there are no "infant mortality" issues before you've actually added it to the array.

 

#2 can be done with ANY good testing utility -- e.g. the manufacturer's diagnostics -- on another system before you add it to UnRAID.    For example, I attach any new drives I buy to a Windows box and use WD's excellent Data Lifeguard for Windows to thoroughly test it -- I do a short test; long test; full write zeroes; then another short and long test.

 

#1 is a nice feature, but as long as you don't mind the time it takes for UnRAID to clear the drive it's no big deal => and of course this is only true if you're ADDING a drive to the array ... there's NO benefit from pre-clearing vis-à-vis the time it takes to do a drive rebuild or parity sync.

 

The main reason for this is that the command line scares the crap out of me, and I have also never been able to find a SIMPLE set of instructions on how to do the pre-clearing.

GUI Plugin