Display Guest’s Boot Message in Host

Apr 1st, 2016 12:00 am

QEMU Commands

virtualized serial port is directed to the host tcp port:1223

qemu-system-x86_64 -enable-kvm -rtc base=utc,clock=vm,driftfix=none -bios bios.bin -device piix3-usb-uhci -soundhw ac97,hda -m 1024 -serial tcp::1223,server,nowait -netdev tap,script=/data/images/qemu-image/qemu-ifup0.sh,id=net0 -device virtio-net-pci,netdev=net0 -hda /data/images/qemu-image/opensuse-50G.raw -name 23 -cpu core2duo -monitor stdio -smp sockets=1,cores=1,threads=1 -vnc :23

Configure Guest GRUB

dmesg | grep ttyS make sure virtualized serial port exists
Make guest display boot message on serial
1. /etc/default/grub/

GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0,9600n8 "
GRUB_TERMINAL=serial
GRUB_SERIAL_COMMAND="serial --speed=9600 -unit=0 --word=8 --parity=no --stop=1"    

2. update grub config

Host connection

Turn of the VM
Add -S in the qemu command to suspend the VM and you can telnet the port
Boot the VM and telnet localhost 1223 after VM is suspended.
Resume the VM in qemu