How to configure and use qemu-guest-agent in Ubuntu 12.04? My main aim is to get the IP address of guest VM from Host machine

Question

In the documentation it is not very clear that how to install and use qemu-guest-agent in Ubuntu 12.04.

So can anyone help me out ?

http://wiki.libvirt.org/page/Qemu_guest_agent

It is a daemon program running inside the domain which is supposed to help management applications with executing functions which need assistance of the guest OS. I want to know the IP address of the guest VM using guest-network-get-interfaces qemu-guest-agent command.

Is there any other way to find IP address of guest VM ?

arp -an, arpwatch ,echo syslog | grep $mac_address is not useful in my scenario ?

Solution

1. First of all install latest version of libvirt-bin(>=1.0.0) on the host system. Installing libvirt-bin(>=1.0.0) on Ubuntu12.04 is itself a challenge because of dependencies.This link may help to do so: https://tad-do.net/2013/02/22/testing-new-libvirt-features-on-ubuntu-12-04/

   Then execute following commands on host:

   mkdir -p /var/lib/libvirt/qemu/channel/target
   chown -R libvirt-qemu:kvm /var/lib/libvirt/qemu/channel
   

2. Add the following to the bottom of /etc/apparmor.d/abstractions/libvirt-qemu:

   /var/lib/libvirt/qemu/channel/target/* rw,
   

3. Install qemu-guest-agent in guest VM.

   sudo apt-get install qemu-guest-agent
   

4. virsh edit VMNAME and add following lines in the devices:

   <channel type="unix">
     <source mode="bind"/>
     <target type="virtio" name="org.qemu.guest_agent.0"/>
   </channel>
   

5. Shutdown and start the VM and execute following command to get the IP Address. There are many other things which can be done using guest-agent.

   virsh qemu-agent-command VMNAME '{"execute":"guest-network-get-interfaces"}'
   

References:http://wiki.stoney-cloud.org/wiki/Qemu_Guest_Agent_Integration

Comments

[David Corsalini]

the guest agent can be contacted via the monitor commands, all the commands are prefixed with guest-. Not sure abut the IP, in oVirt it's done by another agent

[Nehal J Wani]

If your main aim is to get the IP address, then see serverfault.com/a/676257/140905