Fixing Sun Oracle (HGST) 8TB drives reporting 7.86TB

Just had to use this on some 10TB HGST SAS3 drives received from Bitdeals.tech. Super handy.

Did this natively in Unraid.

To reiterate:
sdX < Change this to whatever the device is labeled

sg_readcap /dev/sdX
sg_format --format --size=4096 /dev/sdX
sg_readcap /dev/sdX

Afterwards the second readcap command displays the correct drive size.

Without being super specific to the timing, it takes me <8h to reformat a 10TB drive.

Edit : Yes you do in fact have to keep the session open while it does the long slow format. Either use tmux, screen, or don’t reboot your computer.

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