pfSense

Jim Pingle wrote in #note-1:

Also note that adding a serial port to the VM hardware in Proxmox VE works around the issue. VMs with a serial port present, even if it's not active in the OS, boot properly every time. We'll be including a note to this effect in the documentation.

Docs update commit: https://gitlab.netgate.com/docs/pfSense-docs/-/commit/1843af9eb9315267d39cd159768e0f442db7a5e8

Relevant pages in docs:

• http://docs.netgate.com/pfsense/en/latest/troubleshooting/boot-issues.html#efi-boot-issues
• http://docs.netgate.com/pfsense/en/latest/recipes/virtualize-proxmox-ve.html#booting-uefi
• http://docs.netgate.com/pfsense/en/latest/releases/23-09-1.html#efi-issue-on-proxmox-ve
• http://docs.netgate.com/pfsense/en/latest/releases/2-7-2.html#efi-issue-on-proxmox-ve

Those are now live in the public docs.

You might want to expand where that is referenced in the documentation. It is not 'just' VM's that can have the issue. I have a hardware firewall appliance (XCY). Since I was not using it, I had disabled the serial console redirection, AND the associated serial port. That triggered the issue reported here. Enabling the serial port allowed the system to boot properly.

https://forum.netgate.com/topic/184756/clean-install-of-2-7-2-fails-to-boot

This also occurs in the online upgrade process (in this case on PVE 8.1.10).
22.05 --> 23.01 (success)
23.01 --> 23.05.1 (success)
23.05.1 --> 23.09.1 (EFI framebuffer fail)