On Wed, Jun 4, 2014 at 7:40 PM, Timo Schöler <timo@xxxxxxxxxxxxx> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA256 > > Hi list, > > I searched the web for bug reports regarding this phenomenon I see on > *multiple* machines of a customer, however, I didn't find an exact > fit. So, I'd like to ask here whether anyone else has run into this. > > I have multiple CentOS 6 machines running using KVM to virtualize a > bunch of machines on them (LVM-based). > > Software releases as following: > > [root@fe00 ~]# rpm -qa|egrep '(virt|kvm)' > virt-viewer-0.5.6-8.el6_5.3.x86_64 > libvirt-python-0.10.2-29.el6_5.7.x86_64 > libvirt-client-0.10.2-29.el6_5.7.x86_64 > qemu-kvm-0.12.1.2-2.415.el6_5.8.x86_64 > libvirt-0.10.2-29.el6_5.7.x86_64 > python-virtinst-0.600.0-18.el6.noarch > > [root@fe00 ~]# uname -r > 2.6.32-431.17.1.el6.x86_64 > > The VMs (here: two) have the "default" connection provided by KVM > (heading to the internet) as well as a bridged interface to connect to > a high performance backbone, where sensitive data is kept and > bandwidth is an issue (or better, not :), on a second interface within > the VMs: > > [root@fe00 ~]# brctl show > bridge name bridge id STP enabled interfaces > br1 8000.001b21xxxxxx yes eth1 > vnet1 > vnet3 > virbr0 8000.525400xxxxxx yes virbr0-nic > vnet0 > vnet2 > > br1 is the interface connected to the backbone, virbr0 KVM's user mode > network. > > After some time of inactivity on the virbr0 interface, from *within* > the VMs connection is *lost*. The interface(s) lose their IP; running > dhclient(8) is not of any use. > > To get the machine back onto track, ``service libvirtd restart'' has > to be issued: Vanished iptables rules show up again. (This, in > contrast to an Ubuntu document [0], fixes it without shutting the > VM(s) down.) Starting dhclient(8) within the VMs gets connectivity back. Have you verified that the iptables rules disappear? That is: * Initially, the NAT rule is present * After inactivity, the NAT rule disappears * After restarting libvirtd, the NAT rule re-appears? -George _______________________________________________ CentOS-virt mailing list CentOS-virt@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos-virt
