I have the same problem with new installation OPNsense 20.7 in Proxmox 6.2-11.
Previous version OPNsense 20.1 starts normal, but when upgrade to 20.7 again reboots in circle. U can see the last message before reboot in attachment.
Previous version OPNsense 20.1 starts normal, but when upgrade to 20.7 again reboots in circle. U can see the last message before reboot in attachment.