Re: [libvirt-users] Problem with net-define using Open vSwitch bridge

So, looks like a permissions problem.. From /var/log/libvirt/libvirtd.log: 2013-04-08 16:58:53.897+0000: 6743: info : libvirt version: 1.0.4 2013-04-08 16:58:53.897+0000: 6743: error : virCommandWait:2315 : internal error Child process (/usr/local/bin/ovs-vsctl --timeout=5 -- --may-exist add-port vl20-ovsbr0 vnet0 -- set Interface vnet0 'external-ids:attached-mac="52:54:00:10:B0:EE"' -- set Interface vnet0 'external-ids:iface-id="6e4a326a-1595-e712-15ec-c4905725663e"' -- set Interface vnet0 'external-ids:vm-id="67e7842b-a47b-54df-bb7c-aca75368cd45"' -- set Interface vnet0 external-ids:iface-status=active) unexpected exit status 1: libvirt: error : cannot execute binary /usr/local/bin/ovs-vsctl: Permission denied 2013-04-08 16:58:53.897+0000: 6743: error : virNetDevOpenvswitchAddPort:136 : Unable to add port vnet0 to OVS bridge vl20-ovsbr0: Operation not permitted 2013-04-08 16:58:53.937+0000: 6743: error : virCommandWait:2315 : internal error Child process (/usr/local/bin/ovs-vsctl --timeout=5 -- --if-exists del-port) unexpected exit status 1: libvirt: error : cannot execute binary /usr/local/bin/ovs-vsctl: Permission denied But ovs-vsctl does have read+exec set for 'others': # ls -la /usr/local/bin/ovs-vsctl -rwxr-xr-x 1 root root 3930719 Feb 26 17:12 /usr/local/bin/ovs-vsctl What else is needed? The reason I want to use OVS "fake bridges" is to keep it simple for the team that will be using this virtualization server. If they just select the correct libvirt network (which is tied to the OVS "fake bridge") then the ports will be automatically tagged with the correct VLAN. (I think of OVS fake bridges as something akin to VMware "Port Groups" on an OVS level.) I have defined libvirt networks as detailed in Kyle's blogpost you referenced, but there does not seem to be a way in the virt-manager UI to select the desired portgroup as defined in the network XML. (Yes, you can edit the VM's XML config and hack the portgroup into there, but that's not what I want these users to have to do...) Thanks again for your assistance! Will -----Original Message----- From: sendmail [mailto:justsendmailnothingelse@gmail.com] On Behalf Of Laine Stump Sent: Tuesday, April 09, 2013 10:47 AM To: libvirt-users(a)redhat.com Cc: Will Dennis Subject: Re: [libvirt-users] Problem with net-define using Open vSwitch bridge On 04/08/2013 05:20 PM, Will Dennis wrote: This looks fine. Since this is the first time I've heard of an ovs "fake bridge", I can't really say for sure if it works correctly. However, I now see from your 2nd message that the reason for your initial failure was that you were using a version of libvirt (0.9.4) that had no OVS support at all, and that you've since upgraded to libvirt 1.0.4. Meanwhile, the blog post that you reference above as the reason you're using a "fake bridge" is saying that the reason to do this is to overcome some unnamed bug in libvirt's OVS vlan support. That blog entry was written in October 2012, and mentions that "Kyle" (probably Kyle Mestery) had submitted a patch for [whatever the problem was]. I'm unable to determine which bug or which patch they're talking about from that information, but I don't believe there are any open bugs in OVS vlan support, so it must have been pushed and so would definitely be fixed in libvirt 1.0.4. So, my advice is 1) stop using "fake bridges" and 2) use libvirt's ovs vlan support, as described here: http://www.siliconloons.com/?p=305 (It would be useful to make these "fake bridges" work properly though. You can probably find the error message output by ovs-vsctl by looking in /var/log/messages or /var/log/libvirt/libvirtd.log (it will be logged by the libvirtd process). If you can post that message to this thread, maybe someone will understand why it's failing, and we can push a fix for it.)