Strange issue with booting XCP-NG

Danp

@appollonius Found the patch where Citrix backported the fix to XS 7.1 -- https://github.com/xenserver/xen.pg/commit/4629bd92f3d3263da9d7fe304df422e54d56ee56

@r1 @stormi Guessing that they didn't pass this upstream to the Xen folks.

0 committed to xenserver/xen.pg

CA-316240: Fix booting on some platforms without monitor attached

Some platform UEFI firmware doesn't initialize EFI_GRAPHICS_OUTPUT_PROTOCOL
instance if there is no physically attached display present. So trying
to use it will result in NULL pointer dereference even before existing
BootServices.

Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>

A Former User

@danp thanks, I might be able to somehow tweak this in the EFI config but not 100% sure. Will check this out asap, otherwise I'll have to leave it to the Xcp-NG team

A Former User

@danp So I have another question, do you think that when I install XCP-NG in BIOS mode that this issue wont arise?

Now I know what the problem might be @stormi could this be an UEFI issue rather than an XCP-NG issue?

r1

@danp said in Strange issue with booting XCP-NG:

https://github.com/xenserver/xen.pg/commit/4629bd92f3d3263da9d7fe304df422e54d56ee56

This seems present for XCP-ng 8.0 and 8.2..

A Former User

@r1 Its still strange though that this problem still persists. As I think there are more people using the Quadro P400.. (Correct me if I'm wrong of course).

A Former User

Do you guys think that this has to do with UEFI? Otherwise I will have to reinstall XCP-NG in BIOS mode instead of UEFI mode...

r1

@appollonius I don't think it is driver issue (POST boot).. We may know more only from serial output.

Are you able to boot as-is in BIOS mode without reinstall?

A Former User

@r1 I could try that, will update when that has been done...

A Former User

@r1 How do I boot in BIOS mode without a reinstall? Can that even be done, because I remember that when I installed xcp-ng I had to choose between BIOS or UEFI am I correct? (Could be something else though) otherwise if not I can give that a try.

r1

@appollonius I think it will depend on hardware settings. See if you have option to change the mode in motherboard settings?

I don't have physical hardware access to validate this as I mostly use nested virtualization but XCP-ng /boot has required files support both for UEFI and BIOS mode.

Maybe @stormi can confirm.

A Former User

@r1 If this could be confirmed I would be happy to test it, otherwise I'll have to do it when I have a new system.. Because I dont want to mess up the current one just yet

r1

@appollonius I don't think there is any harm. You will be either be able to boot or not. You can always switch back to old settings.

A Former User

@r1 Alright then I will give it a try somewhere today

stormi

Unless I'm mistaken, XCP-ng installed in UEFI mode won't boot in bios mode. There won't be anything written in the MBR.

A Former User

@stormi Ahh... So I would have to reinstall XCP-NG completely to be able to boot in BIOS?

stormi

@appollonius yes

A Former User

@stormi Damn... And that all to 'test' if the GPU is working in BIOS mode.

A Former User

Maybe I asked the wrong question here, but is the NVIDIA QUADRO P400 even supported? Maybe that could be an issue as well? If not I think I'll have to grab something like a Radeon WX2100..

stormi

It's not supported for vGPUs https://xcp-ng.org/docs/compute.html#vgpu but it should not prevent other uses of XCP-ng in theory.

A Former User

@stormi Ahh thanks for the webpage, though I still think BIOS mode wont fix this issue I believe.. So I will capture the serial output, to see what happens.