Install

This assumes that the bridge br0 has already been set up, and that the necessary packages have been installed.

For permissions reasons (probably not the only or best way to deal with this), /usr/share/qemu/ovmf-x86_64-code.bin has been copied into /home/roger/kvm-machines/efi-bios/

As user roger, (not root):

qemu-img create -f qcow2 /home/roger/kvm-machines/name.qcow2 16G

qemu-system-x86_64 -machine accel=kvm                        \
      -hda /home/roger/kvm-machines/name.qcow2 -m 2048       \
      -bios /usr/share/qemu/ovmf-x86_64-code.bin             \
      -net nic,model=virtio                                  \
      -net bridge,br=br0,helper=/usr/lib/qemu-bridge-helper  \
      -monitor stdio

It should now be able to PXE boot and get installed.

If you have the right logic as described there in the DHCP and TFTP server, you can also install non-EFI systems by omitting the -bios option above.)

Import

Then import it:

virt-install --name name --memory 2048                  \
             --disk /home/roger/kvm-machines/name.qcow2 \
             --import

After it fails (which it will, if it’s an EFI machine), edit /home/roger/.config/libvirt/qemu/name.xml

Or, using virsh:

virsh edit name

In <os>...</os>

add:

    <loader type='pflash'>/home/roger/kvm-machines/efi-bios/ovmf-x86_64.bin</loader>

And also copy /usr/share/qemu/ovmf-x86_64-code.bin to /home/roger/kvm-machines/efi-bios/ovmf-x86_64.bin

Otherwise we see permissions errors (I’m sure there are better ways of solving this, but it works.) Also for some systems it seems necessary to provide a separate per-machine copy of ovmf-x86_64.bin (see section "Booting Problems" below ).

In interface we need to change to:

<interface type='bridge'>
...
  <source bridge='br0'/>
...

Getting a console

Getting virsh console to work:

Inside the virtual machine, edit /etc/default/grub.

Add console=ttyS0 to GRUB_CMDLINE_LINUX_DEFAULT

Then run grub2-mkconfig -o /boot/grub/grub.cfg

On older systems make the equivalent bootloader changes.

Also make sure that a getty is available on ttyS0 (on systemd setups this will happen automatically).

On systems with /etc/inittab it needs to be enabled there:

S0:12345:respawn:/sbin/agetty -L 9600 ttyS0 vt102

Mounting the disk image

Or, you could temporarily edit the default entry in /boot/grub/grub.cfg externally by mounting the disk image…

But… kpartx won’t work with qcow2 images

So install guestfs-tools and then use:

guestmount -a tumbleweed.img -m /dev/sda3 /mnt

Or, you can use:

modprobe nbd
qemu-nbd --connect=/dev/nbd0 /home/roger/kvm-machines/name.qcow2

and then proceed using kpartx -a /dev/nbd0 and mount the relevant partitions that appear under /dev/mapper/

(Reference for mounting partitions in qcow2 images: http://ask.xmodulo.com/mount-qcow2-disk-image-linux.html)

Remote viewing

For remote graphical viewing using remote-viewer:

   <graphics type='spice' autoport='yes' listen='0.0.0.0'>
      <listen type='address' address='0.0.0.0'/>
   </graphics>

Monitoring

To enable monitoring you can install the qemu-guest-agent package and add the following to the XML to make it work (you also need to enable the service qemu-guest-agent provides, or start qemu-ga from /etc/init.d/boot.local according to the operating system version):

   <channel type='unix'>
      <target type='virtio' name='org.qemu.guest_agent.0'/>
   </channel>

This lets you externally discover the running virtual machines' IP addresses for example, using

virsh domifaddr --source agent <name>

Script to get all addresses

#! /usr/bin/env python
from pexpect import run
###############################################################################
machines = []
for i in run('virsh list').split('\n')[2:]:
    if len(i) > 1:
        machines.append(i.split()[1])
machines.sort()
###############################################################################
for m in machines:
    print m.strip().ljust(14),
    o = run('virsh domifaddr --source agent ' + m).split('\n')[2:]
    if len(o) >=6:
        for line in o:
            if '192' in line:
                print line
    else:
        print ' '
###############################################################################

Output:

$ getvmadds.py
sles11sp3       eth0       52:54:00:93:c0:ee    ipv4         192.168.1.153/24
tumbleweed      ens3       52:54:00:a9:29:3d    ipv4         192.168.1.147/24

Booting problems

At least for older (pre-grub2 / elilo) systems like SLES 11 using EFI, it seems that one needs to store a separate copy of the EFI BIOS per machine and reference that in the XML, e.g.:

    <os>
      [...]
      <loader type='pflash'>/home/roger/kvm-machines/sles11sp3-ovmf-x86_64.bin</loader>
      <boot dev='hd'/>
    </os>

Otherwise the BIOS may "forget" how it’s booting and we drop to the EFI shell at startup after booting a different machine.