Configuring Openstack images to write in console.log

If you want to see booting process and kernel output in openstack console.log file you need to modify kernel params. By default "quiet splash" in kernel parameters. You need to delete it  and add "console=ttyS0". It will output to first serial port console. By default serial port 1 is set in libvirt xml files.


<console type='file'>
  <source path='/mnt/drbd0/nova/instances/instance-00000044/console.log'/>
  <target type='serial' port='1'/>
</console>

Ubuntu:

Edit /etc/default/grub:

....
GRUB_CMDLINE_LINUX_DEFAULT="console=ttyS0"
...
GRUB_TERMINAL=console
...

Then type "update-grub" to generate new grub.cfg. Tested on Ubuntu 11.04, 11.10

Fedora:
Edit /etc/grub.conf. Remove "quiet spalsh" params and add "console=ttyS0". Tested on fedora 14, 15.

Tested on libvirt-0.9.1-1.fc15.x86_64

To see what write to file

du -h /var/lib/nova/instances/instance-00000015/console.log