Is there an equivalent way to preclear a disk outside of the system?

I'm primarily interested in the stress test as that has uncovered potentially sub-quality disks several times for me. I have a test rig with available ports that would be really easy to use. My server doesn't have any extra mounting locations (but does have 2 more sata ports).

I've read about using bad-blocks and the linux dd command, but I don't know enough to know if that's the right path.

Any ideas?

WD Lifeguard / Seagate SeaTools / SMART Extended tests

 

But none of them ( or any other 3rd part equivalent ) will write the appropriate signature that indicates the drive has been precleared, so unRaid will still want to clear it or you will need to preclear it again.

 

Alternatively, set up a trial key for the test rig and preclear the drive there.  It will be valid for the main rig.

I usually use

badblocks -v -w -s -b 4096 /dev/sdX

to test new and suspect disks thoroughly. The options are simply explained here. Essentially, -v makes it verbose, -s makes it show progress, -b 4096 set the block size which seems to be needed to make it work on high capacity disks, and -w means a destructive read/write test that fills the entire disk with different patterns in four passes and checks whether it can read them.