6 Steps From FreeNAS (USB) to TrueNAS CORE (SSD)

Last week I talked about adding the Plugadget 2.5″ mounting bracket PC cards to my file server. I’ll be switching from FreeNAS on mirrored USB flash drives to TrueNAS CORE on mirrored SSDs in six steps. Since my motherboard has a legacy BIOS, step number four took a lot longer than it should have.

Step 1 – Download FreeNAS Config File

FreeNAS GUI

The first step is to download the FreeNAS config file from my file server.

With the FreeNAS GUI in the web browser, I clicked on System, General, and then the “Save Config” button. I clicked on the boxes for “Export Password Secret Seed” and “Export Pool Encryption Keys” in the dialog box. I saved the config file to the download folder of my editing PC.

Step 2 – Remove USB Flash Drives

FreeNAS Boot Drives

The second step is to remove the USB flash drives.

I shut down the system, pulled out the 8GB SanDisk Cruzer Fit USB flash drives, and put them aside for safe keeping. If I don’t upgrade the ZFS storage pool on my hard drives, I can always plug in the USB drives and boot up FreeNAS. After I’m confident that TrueNAS is working fine, I’ll update the ZFS storage pool.

Step 3 – Install SSDs

The third step is to install the SSDs.

I installed a pair of Adata 120GB SSDs into the new 2.5″ mounting bracket PC cards. The smallest SSD recommended for a TrueNAS boot drive is 16GB. Smaller SSDs cost about the same as a 120GB SSD at $20 US or so. Since the motherboard is micro-ATX, I installed the PC cards in the empty bottom slots.

I needed four cables from my junk box:

  • The Molex power cable for the Seasonic 620W modular power supply.
  • A Molex-to-SATA power splitter.
  • A pair of SATA data cables with straight connectors.

SATA ports 0 through 3 were difficult to access behind the SAS and power cables for the hard drives. I plugged the data cables into ports 4 and 5 on the motherboard since they were more accessible. All the cables got tucked away into the bundle at the bottom of the case and behind the hard drives.

Step 4 – Fiddle Legacy BIOS

Legacy BIOS Screen

The fourth step is to fiddle with the legacy BIOS to recognize the new SSDs.

When I booted up the system, the BIOS couldn’t find the SSDs and tried to boot one of the hard drives. I forgot that I turned off the SATA ports in the BIOS after I installed the SAS controller card two years ago. I turned on the SATA ports in the BIOS and rebooted the system. That didn’t work either.

After a couple hours of fiddling around with the BIOS, I pulled the CMOS battery, and reloaded the defaults for the BIOS. This time the BIOS screen found the SSDs. I booted the USB flash drive with the TrueNAS CORE installer.

Step 5 – Install TrueNAS CORE

TrueNAS CORE 12 Installer

The fifth step is installing TrueNAS CORE on to the SSDs.

After I selected the SSDs as mirrored boot drives, I got prompted to upgrade the install or do a fresh install. I had installed TrueNAS on the SSDs from my test PC as a test run. I selected a fresh install.

The next screen asked if I wanted to upgrade the boot environment or reformat the drive. I selected to reformat the SSDs.

I got prompted to enter the root password.

The next screen prompted if I wanted to boot via UEFI or the BIOS. I selected boot via the BIOS.

The final screen prompted if I wanted to create a 16GB swap partition on the boot drives. I selected yes.

After the installer finished, I got prompted to remove the USB stick and reboot the file server.

Step 6 – Upload FreeNAS Config File

TrueNAS CORE GUI

The sixth step is to upload the FreeNAS config.

I pointed my web browser to the IP address that the file server booted up with and logged into the web-based GUI. I clicked on System, General, and then “Upload Config” button. I uploaded the FreeNAS config file and rebooted the file server.

The settings migration FreeNAS to TrueNAS didn’t take long since I had a very simple set up. I didn’t have any containers, jails, or virtual machines.

When the file server came back up, everything behaved as if I was still running FreeNAS.


A week after running TrueNAS CORE on my file server, I got an email notification that the first SSD has unreadable sectors. Not surprising. These are old SSDs pulled out of my junk box. If the first SSD fails, the file server will boot off the second SSD. I should have a pair of 240GB SSDs in my junk box.

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