Having startup messages on virtual tty (monitor) AND serial console

Question

I have enabled serial console over null-modem cable in Debian 10 like this:

/etc/default/grub:

GRUB_CMDLINE_LINUX="console=ttyS0,115200n8"
GRUB_TERMINAL=console

then systemctl enable [email protected].

That was all there was to it. However, while now I can see all the startup messages over serial (initial kernel messages and systemctl service start messages), nothing is displayed on monitor (virtual tty) until login prompt appears.

Is it possible to have those startup messages displayed on both monitor and over serial connection?

Answer 1

Yes, specify console= twice in the kernel command line.

GRUB_CMDLINE_LINUX="console=tty0 console=ttyS0,115200n8"