[Pkg-libvirt-maintainers] Bug#587484: Bug#587484: libvirt0: routing setup (iptables) relies on working DNS

[Guido Günther]

Hi Daniel,
On Tue, Jun 29, 2010 at 02:06:32AM +0200, Daniel Friesel wrote:
> Package: libvirt0
> Version: 0.8.1-2
> Severity: normal
> 
> 
> Setup:
> libvirt with qemu, network managed by libvirt.
> 
> Problem:
> When starting libvirt VMs when no working DNS is available, virsh is unable to
> connect to libvirt and simply hangs without saying anything.
> Adding the IPs configured for the VMs and corresponding (fake) hostnames to
> /etc/hosts and then restating libvirt fixes this issue.
> 
> It looks like this is because the iptables calls made by libvirt to set up VM
> routing do not use the -n option. So, if all DNS servers for one (or more) VM
> IPs are unreachable, iptables waits a long time until reaching a timeout, and
> in this time libvirt is completely unusable.
> 
> I propose to use "iptables -n" every time iptables is called by libvirt. It
> should not have any negative effects and would save a lot of trouble and
> debugging in case of DNS fuckups.
Could you check with strace where your libvirtd actually hangs? 
 -- Guido