# How To Setup Another Bootdisk



## fr33bsd (Aug 21, 2021)

Hi,

imagine you install FreeBSD 13, but your HBA/SAS/SATA-Controler cannot install its BIOS, so booting from that device is impossible as you will witness.

But you can setup another disk to be new boot disk booting your installation.

*This is not working with encrypted zroot pool!*

Assuming you have FreeBSD on a mirrored disk setup, `da0` `da1`.
Your new boot disk might be `ada0`.

Use live system after FreeBSD installation (bsdinstall) or just boot some live system.

Switch to root.

Enter the commands to set up the new boot disk:

`fdisk -BI /dev/ada0`
`bsdlabel -B -w ada0s1`
`newfs -U -O1 /dev/ada0s1a`

Install boot loader:
`boot0cfg -v -B -t1 ada0`

Mount your installation (if it is not already mounted) and mount your new boot disk:
`mount /dev/ada0s1a /mnt`

Assuming that your installation is mounted to  /live copy the boot directory on the new boot disk:
`cp -r /live/boot /mnt`

Make your kernel mount your pool that is on `da0` and `da1`:
`echo 'vfs.root.mountfrom="zfs:zroot:/ROOT/default"' >> /mnt/boot/loader.conf`

`umount /mnt`

*Do not forget to switch to your new boot device in your BIOS after reboot*.

So, what do you have in the end? Now, you have a new thin boot device, containing essential stuff to boot the system. Footprint is approx. 80MB.

Enjoy.


----------



## fr33bsd (Aug 22, 2021)

If you want to use geli go for this solution.


----------

