[jan-jaap]

It took me 2.5 hours to sequentially write a 300gb disk on an Octane.

Sounds about right. The SCSI bus on an Octane has a theoretical max of 40MB/s but you never reach that; ~ 35MB/s is to be expected (with a disk capable of that). 35MB/s equals roughly 2GB/min, so 150minutes for a 300GB disk. All as expected, it seems.

I'm using drives that are 70 plus gigs usually.

It takes forever even doing the sequential and I've never actually had it erase data. Maybe I'm not doing something right but yeah, how I would do it if I could fix the miniroot would be to have a /dev/zero type device that can just sequentially blast zeros and then mkfs.

What you want to do (from the 'fx' prompt) is: 'exe'rcise > 'seq'uential > wr-o. Then select 0 as the start and <whatever big number fx suggests> as the end address, and you will overwrite the entire disk. Exactly what /dev/zero would do and only limited by the hardware. Stay away from random or butterfly tests. If you do a write-compare test, it will write a block, then read it back to verify. That means a reasonable amount of head movement as well.

Before you leave 'fx' you will have to create a new disk label on your freshly wiped disk.

Low-level formatting should not be necessary unless maybe if you suspect hardware failure. Never to get rid of data. It takes a long time and if for whatever reason it's interrupted the disk is usually bricked.