Enabling 'systemd' Debug Shell During Boot
systemd related boot issues, you can enable early shell access during boot.
Perform the following steps to enable early shell access:
Restart the Photon OS machine or the virtual machine running Photon OS.
When the Photon OS splash screen appears, as it restarts, type the letter
systemd.debug-shell=1to the kernel command line.
Optionally, to change logging level to debug, you can append
F10to proceed with the boot.
Alt+Ctrl+F9to switch to
tty9to access the debug shell.