How to take xml file of running instances in openstack?

Question

Im trying to edit xml file of running instances in openstack but couldn't able to find out where it is placed .

When i tried with #virsh list -all

Which is listing some vms which is not created via openstack

Please someone help me out to take xml of running instances in openstack.

Answer 1

There are several different libvirt instances, and virsh will auto-detect a connection. If you run virsh as root it'll connect to qemu:///system while if you run it as non-root it'll connect to qemu:///session. OpenStack / Nova will be using qemu:///system. If you want to make this explicit tell virsh which to use virsh -c qemu:///system list --all should show you the VMs.

A further complication is that some deployments of OpenStack will put libvirt and QEMU inside a container, so if you run virsh in your host, it won't be able to access the libvirt/QEMU inside the container. You would need to find which container its using, enter the container namespaces, and then run virsh inside the container.

Answer 2

You also should consider that openstack nova assembles the resulting xml file from its database from multiple sources. So even if you edit the final xml file on the hypervisor your VM will lose the changes after restart (if it even starts with those changes). You need to find the properties you want to change and edit the respective nova.conf settings, image properties and so on.