(11.2-U5) Migrating freenas-boot from a single drive to a mirrored pair


Jul 22, 2019
Currently my freenas-boot zpool is on a single SSD drive. I am worried that this SSD drive is a single point of failure. What I would like to do is install 2 new drives and have freenas-boot use those instead. I imagine the process would be to first mirror freenas-boot to one of the new drives, then do the same with the other new drive, and finally remove the old drive from the zpool.

Are there instructions for how to do this on FreeNAS 11.2(-U5)? Similar questions have been asked in the past, but they are for FreeNAS version 9.X.

The freenas-boot pool is hidden from the GUI "Storage -> Pools" page, probably by design. There doesn't seem to be any other place to access it's info from the GUI. I can however see the Boot Drive listed in the "Storage -> Disks" section, but no way to alter the pool is provided there.

I could add the new drives from the command line, but I'm sure there are bootloader-related steps that need to be taken as well. Does anyone know what they are?


Apr 15, 2018
Is there any reason one should mirror the OS boot drive from within FreeNAS vs just using the motherboard onboard RAID controller to create a RAID1 mirror and install the OS to that?