BIOS + GPT = PUKE

[clarknova]

I'd like to just take this opportunity to point out that there are a number of stale threads in this forum that describe, but fail to identify what appears to be a common problem.

The problem is the result of a combination of the facts that

1. FreeNAS 9.3+ installs itself on a GPT boot device, but relies on BIOS or CSM implementations to boot.
2. GPT being part of the UEFI specification, generally relies on UEFI firmware to act as a proper boot device.
3. While some motherboards and their firmware manage to boot FreeNAS's GPT disk from BIOS or CSM just fine, many do not.

There are a handful of unsolved threads in these forums that, in my estimation, describe this problem.

1. https://forums.freenas.org/index.php?threads/freenas-usb-boot-on-uefi-garbage.38916/
   
2. https://forums.freenas.org/index.php?threads/uefi-boot-failure-for-new-install.39258/
   
3. https://forums.freenas.org/index.php?threads/fail-to-see-boot-device-after-install.35163/
   
4. https://forums.freenas.org/index.php?threads/freenas-wont-boot-on-usb-stick.30228/

All of these threads unfortunately lack a clear description of the problem or a simple solution. Instead, they are mostly full of the familiar advice of "you need ECC RAM", "your board doesn't UEFI well", "your board isn't on the FreeBSD compatibility list" and the like.

Fortunately, there is one golden thread that manages to get down to the meat of the matter.

1. https://forums.freenas.org/index.php?threads/freenas-stable-9-3-unable-to-boot-usb.28103/

All five of the threads I have linked to are basically stale, and the latter, which actually gets down to the problem and offers a workaround, is old enough and long enough that many people will miss it. Further, the described workaround is "So Ugly You'll Tear Your Eyes Out"*, and not effective in all cases.

*http://www.rodsbooks.com/gdisk/hybrid.html

So my hopes in starting this thread are that

1. People having this problem now and in the future will find this thread and gain a proper understanding of the problem
2. People issuing the old and irrelevant advice will stop parroting and come to the table
3. FreeNAS developers will recognize the issue and contribute to a solution.

keywords: no boot device usb not found unbootable after install

 

[gpsguy]

Open a ticket on bugs.freenas.org and and post a link here, to your bug ticket.

The developers don't participate on the forum.

With rare exceptions the folks providing support on the forums are just volunteers and have no affiliation with iXsystems.


Sent from my phone

 

[clarknova]

Thanks for the suggestion.

https://bugs.freenas.org/issues/13760

 

[Pheoxy]

Not sure if this a fix but it looks like some work is being done.

https://bugs.pcbsd.org/issues/17052

 

[Pheoxy]

More work being done.

https://bugs.pcbsd.org/issues/17899

https://bugs.pcbsd.org/issues/17898

 

[Pheoxy]

Apparently this has been resolved in FreeNAS 10 BETA 2 once its been released. Unfortunately I can no longer test this on my box.

If on release of Beta 2 someone is able to test if this is still a issue? Thanks in advance.

 

[wblock]

GPT being part of the UEFI specification, generally relies on UEFI firmware to act as a proper boot device.

This is a misconception. The PMBR allows BIOS booting on GPT disks. Where it can go wrong is due to bugs in any of several places. BIOS or UEFI implementations that are either overly strict or make assumptions that are outside the standards are a common cause.