Red Hat Bugzilla – Full Text Bug Listing
|Summary:||Unable to run more than 1 guest simultaneously|
|Product:||[Fedora] Fedora||Reporter:||David Aquilina <dwa>|
|Component:||libvirt||Assignee:||Daniel Berrange <berrange>|
|Status:||CLOSED CURRENTRELEASE||QA Contact:||Fedora Extras Quality Assurance <extras-qa>|
|Version:||8||CC:||flanagan, hbrock, jhutar|
|Fixed In Version:||0.4.1||Doc Type:||Bug Fix|
|Doc Text:||Story Points:||---|
|Last Closed:||2008-04-04 12:05:03 EDT||Type:||---|
|oVirt Team:||---||RHEL 7.3 requirements from Atomic Host:|
Description David Aquilina 2007-10-15 18:01:09 EDT
Description of problem: When I attempt to run more than 1 guest at a time, I receive the following error when I attempt to start the second guest: virDomainCreate() failed Failed to add tap interface 'vnet0' to bridge 'virbr0' : Device or resource busy Version-Release number of selected component (if applicable): $ rpm -qa | grep virt libvirt-0.3.3-1.fc8 python-virtinst-0.300.1-1.fc8 virt-manager-0.5.2-1.fc8 virt-viewer-0.0.2-1.fc8 libvirt-python-0.3.3-1.fc8 $ uname -a Linux dalek 2.6.23-5.fc8 #1 SMP Wed Oct 10 19:25:16 EDT 2007 x86_64 x86_64 x86_64 GNU/Linux How reproducible: always Steps to Reproduce: 1. Install 2 guests with shared networking 2. Start 1st guest 3. Start 2nd guest Actual results: Second guest does not start Expected results: Second guest starts Additional info: These are QEMU/KVM guests. Here's the full backtrace: Unable to start virtual machine '<class 'libvirt.libvirtError'> virDomainCreate() failed Failed to add tap interface 'vnet0' to bridge 'virbr0' : Device or resource busy Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/console.py", line 520, in control_vm_run self.vm.startup() File "/usr/share/virt-manager/virtManager/domain.py", line 377, in startup self.vm.create() File "/usr/lib64/python2.5/site-packages/libvirt.py", line 228, in create if ret == -1: raise libvirtError ('virDomainCreate() failed', dom=self) libvirtError: virDomainCreate() failed Failed to add tap interface 'vnet0' to bridge 'virbr0' : Device or resource busy '
Comment 1 David Aquilina 2007-11-05 14:16:57 EST
It seems if you give each guest a unique vnetX device, it works. For the benefit of anyone who comes across this: virsh --connect qemu:///system dumpxml guest-name > /tmp/guest Edit /tmp/guest and replace vnet0 with vnet1 virsh --connect qemu:///system define /tmp/guest
Comment 2 Jan Hutař 2007-11-29 04:59:23 EST
Seems to me, that when "<target dev='vnet5'/>" is missing, it is determined correctly, when I start the system. Am I right? kernel-184.108.40.206-49.fc8 kvm-36-7.fc8 libvirt-0.3.3-2.fc8 libvirt-python-0.3.3-2.fc8 python-virtinst-0.300.1-3.fc8 qemu-0.9.0-5.fc8 virt-manager-0.5.2-2.fc8
Comment 3 Daniel Berrange 2007-12-04 10:36:05 EST
Created attachment 277111 [details] Strip auto-genereted vnetXXXX interfaces The last libvirt release extended the domain XML to include the <target dev="vnetXXX"/> device details, so apps can then lookup I/O stats. Unfortunately, when virt-manager then feeds this XML back into libvirt (eg when changing a VM config param), this auto-generated vnetXXX device node gets saved permanently. There is high liklihood that you'll get a clash between two domains after this has happened a couple of times (depends on exact sequence of ops in virt-manager). This patch strips out the auto-generated vnetXXX devices when starting a guest. If someone would like to this fix, you can apply it to the libvirt source RPM & rebuild. Be sure to restart libvirtd after installing a rebuilt version.
Comment 4 Daniel Berrange 2007-12-04 11:57:46 EST
Created attachment 277161 [details] Strip autogenerated vnet target devs Previous patch was flawed
Comment 5 Daniel Berrange 2008-04-04 12:05:03 EDT
This is fixed in current F8 updates.