FreeNAS – BTX Halted – gptzfsboot: error 4

I upgraded from FreeNAS 11.1-U6 to FreeNAS 11.2 just before Christmas, everything went fine and had been working without an issue. Yesterday I powered off the NAS to relocate it and was unable to get FreeNAS boot, it was getting stuck at boot with the following error:

gptzfsboot: error 4 and BTX halted

FreeNAS is running on a HP Gen8 Microserver, the FreeNAS OS is installed on an SSD using the ODD drive.

I came across a couple of forum posts on the FreeNAS forum which suggest disabling the HP RAID Controller and changing it to AHCI, but when in AHCI mode the Microserver only supports booting from the first HDD Bay, and the onboard SATA port for the ODD is the fifth one.

The workaround I applied was to change the SATA controller mode from AHCI to Legacy and then restart.

After the restart in BIOS you can find two SATA controllers and you can choose one of them. The first one is the controller for the hot swappable bays in front of the server and the second one is for the on-board SATA connector for the ODD bay.

Once changed to legacy & second SATA connector FreeNAS booted straight back up!

9 Comments on "FreeNAS – BTX Halted – gptzfsboot: error 4"

  1. Thank you! My box was rebooted due to a power-outage and I experienced the exact same message.
    Moved my boot-SSD from the 3rd easy swap bay to the odd-slot and enabled legacy support.
    Then I changed the SATA controller order and boom. It was working. Thank you so much!

  2. thanks! switching to legacy just worked like magic

  3. Thanks Jake, appreciate you posting this. I was busy with one server issue, only to find myself having to juggle another! Saved me hours!

  4. Thanks for taking the time to record this, saved me hours of debugging the issue..!

  5. Bloody hell – my google foo was too weak πŸ˜” I only came here after 4 hours of trying various things, nothing worked. You just saved my da…night. Thanks!

  6. You Absolute legend. 2 nights of frustration getting nowhere, 4 USB sticks one HDD and one SSD later and i find this blog… THanks!

  7. Hi, having a Micro HP with bay 1 – 4 occupied with 2 mirror drives, 2 data drives and an SSD on the ODD port, i used Grub2 and BSD USB to boot from, the latter giving problems when updating TrueNAS. Then followed recommendations using the onboard RAID controller, no go. Switching to AHCI also resulted in BTX Halted. Selecting Legacy BIOS did the trick. Many thanks.

Leave a comment

Your email address will not be published.