I have a python script that monitors the VMs on physical host servers running Xen, but the script doesn't work properly on a server I just built with KVM. The script runs as a non-root user and simply gathers some details on the status and names of the domains running on the host. Both Xen and KVM servers are running the same version of libvirt (libvirt-0.6.3-20.1.el5_4) and have the same, default /etc/libvirt/libvirtd.conf config file. To troubleshoot, I've been running python interactively. Here's how my Xen servers behave: $ python Python 2.4.3 (#1, Sep 3 2009, 15:37:37) [GCC 4.1.2 20080704 (Red Hat 4.1.2-46)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import libvirt >>> conn = libvirt.openReadOnly(None) >>> domains = conn.listDomainsID() >>> print domains [0, 3, 15, 16, 21, 24, 26, 30, 32, 36, 38, 41, 43, 45, 47, 49, 51, 55, 63, 67] >>> When I try the same thing on the KVM server: $ python Python 2.4.3 (#1, Sep 3 2009, 15:37:37) [GCC 4.1.2 20080704 (Red Hat 4.1.2-46)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import libvirt >>> conn = libvirt.openReadOnly(None) 14:33:07.303: error : No vport operation path found for host0 14:33:07.320: error : No vport operation path found for host4 14:33:07.325: error : No vport operation path found for host3 14:33:07.367: error : No vport operation path found for host1 14:33:07.368: error : No vport operation path found for host2 >>> domains = conn.listDomainsID() >>> print domains [] >>> (The vport stuff is weird, but I found this posting that suggests its harmless (http://www.mail-archive.com/libvir-list@redhat.com/msg17477.html) so I'm ignoring it.) However, when logged in as root on the KVM server, it works just like my Xen servers: # python Python 2.4.3 (#1, Sep 3 2009, 15:37:37) [GCC 4.1.2 20080704 (Red Hat 4.1.2-46)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import libvirt >>> conn = libvirt.openReadOnly(None) >>> domains = conn.listDomainsID() >>> print domains [1] Again, on the KVM server, plain old "virsh list" with the debug level set to "2" $ export LIBVIRT_DEBUG=2 $ virsh list 14:21:06.532: error : No vport operation path found for host0 14:21:06.550: error : No vport operation path found for host4 14:21:06.555: error : No vport operation path found for host3 14:21:06.598: error : No vport operation path found for host1 14:21:06.599: error : No vport operation path found for host2 14:21:06.615: info : No security driver available Id Name State ---------------------------------- Permissions in /var/run/libvirt: # ls -ld /var/run/libvirt/* srwx------ 1 root root 0 Feb 5 08:53 /var/run/libvirt/libvirt-sock srwxrwxrwx 1 root root 0 Feb 5 08:53 /var/run/libvirt/libvirt-sock-ro drwxr-xr-x 2 root root 4096 Jan 21 14:38 /var/run/libvirt/network drwxr-xr-x 2 root root 4096 Oct 20 18:50 /var/run/libvirt/qemu Can someone provide some tips on what else I can check, if this might be a bug, or point out any mistakes that I might've made? Any help is appreciated. Thanks, Tom