OpenBSD as KVM Guest

# Add guest agent package

pkg_add qemu-ga

# Add to autostart

rcctl enable qemu_ga

Qemu-ga reads its settings from /etc/qemu/qemu-ga.conf. I prefer to write logs to file instead of STDERR for reading logs after system start.

Config sample:

   [general]
   method=isa-serial
   path=/dev/tty00
   verbose=1
   logfile=/var/log/qemu_ga.log

# Let boot logs go to serial console

echo "set tty com0" >> /etc/boot.conf

# Allow your serial console in /etc/ttys.

It’s where getty finds information about consoles for login prompt, so you can run virsh console.

Do not add “secure” at end of line if you don’t want cloud admins to bruteforce your root password. Final record should look something like this:

tty00 "/usr/libexec/getty std.9600" vt220 on

You can get and change serial console settings via stty stty -a -f /dev/tty00

See also this article.