i need to preclear 4 2TB drives to replace 4 1TB that i'll be using on a different build.

 

can i run preclear on osx, and should i pay special attention to 4K alignment.

 

if not binary compatible ... maybe, run a vm with ubuntu or even slackware and run preclear from there ?

Easiest way is to prepare another unraid usb stick and just boot off of that. I don't know if unraid will run on a mac, but since macs are x86 based now, I don't see why not.

it (unRAID) will probably run in a vm. 

 

Use the "-A" (4k-aligned) alignment UNLESS they are WD EARS disks with a jumper added.

 

The preclear script is likely to run under other versions of linux, but unless run under unRAID, it is not going to be able to protect yourself from clearing a disk it should not.  Do be careful...  (hate it when you ask it to write zeros over your entire osx drive)

thanks for the replies

 

they are EARX drives, no jumper.

 

i'll try the unraid vm route first, if that doesn't work, i'll do it in another machine that's being prepared for another build.

I would try it. OS X being based on BSD it may work. As others have said, just make sure you choose the correct drive!

I've tried to run pre clear in Mac OS X 10.7.4 (Lion), but there is a long list of things that need to be installed in order for it to work correctly. I haven't gotten it to work yet. Virtual machines in parallels do not allow for low level device communication, so this would not work as a solution for installing unRAID in a virtual machine.

 

However, I have not tried unRAID using VMWare. This may or may not work; for it to work, not only would you need to be able to create an unRAID virtual machine, but VMWare would need to allow you to have direct device access instead of mounting through the underlying OS.