IT Mode

Flashing a SAS controller to IT Mode configures the SAS controller to provide the operating system with direct access to each of the attached drives; instead of a single RAID device managed by proprietary software. Using IT Mode provides greater flexibility, manageability, and portability. Tools are provided to build a FreeDOS USB image that comes bundled with the necessary software and helpful scripts to switch your SAS controller over to "IT Mode".

Preparing the FreeDOS Image

Debian Dependencies

apt install curl p7zip mtools

Prepare the image

git clone https://git.15h.org/rane/itmode.git
cd itmode
make

Write the image

Write the prepared FreeDOS image (ITMODE.img) to a flash drive using your preferred method. For example, with dd:

dd if=./ITMODE.img of=/dev/sdc bs=4M status=progress

Flashing to IT Mode

Supermicro H8DCL-6 / H8DG6 / H8QG6

Step 1, Record SAS Address

There will be a sticker on your motherboard that lists your SAS address (ie: 500605B0xxxxxxxx). Write this value down.

Step 2, Wipe

wipe_supermicro
reboot

Step 3, Flash

Enter your SAS address when requested.

flash_supermicro