> I upgraded from CentOS 5.9 to CentOS 6.4. > > I try to reuse my virtual machines and am only partially successful: I > can run them, I just cannot get the network OK and need some help with that. > > > What I had in the past was pretty simple: both the host and the VM?s > used eth0 and each had an IP in the same subnet and could communicate freely. > With the new install it seems somewhat more complex and I think I need to configure a bridge and use that. > Unfortunately, info I find through google is overwhelming and > confusing. All examples either configure something else, or the outcome is not what? expected. > > > So: how to go about setting things up to have say: > > My physical machine is on 192.168.0.90 > > My Virtual machines are on 192.168.0.100 and 101. > > These are to be fixed addresses. > > The 2 VM?s have to communicate with each other and with the physical machine. > > The VM?s do not necessarily need to communicate with the rest of the world. > > The physical machine needs to communicate with the rest of the world. > > > I use: > > - CentOS-6.4_64 > > - Virtual Machine Manager 0.9.0 > > - xen 4.2.3 > > - libvirt 0.10.2.7-5 > > - VM?s show Hypervisor = xen (fullvirt) > > - Emulator = qemu-dm > > - NIC points to Shared device name virbr0 > > - on the host, virbr0 has IQ 192.168.122.1 > > > I have been fighting this for 2 weeks, now. I tried to follow several > advises which resulted in either the VM?s not connecting to anything, > or my host losing its connection to the rest of the world, or both. So either I still do something not-right, or I follow the wrong gidelines. > > > Can someone give me a push in the right direction, please? Thanks to all who responded to this: it is working now. Solution was relatively easy and mainly a matter of understanding the "ifcfg-eth0 - like" files. What I did: 1 - yum install bridge-utils 2 - change /etc/sysconfig/network-scripts/ifcfg-eth0 to: DEVICE="eth0" BOOTPROTO=none ONBOOT="yes" TYPE="Ethernet" HWADDR=xx:xx:xx:xx:xx:xx BRIDGE="br0" USERCTL=no IPV6INIT=no NM_CONTROLLED="no" 3 - change change /etc/sysconfig/network-scripts/ifcfg-br0 to: DEVICE="br0" BOOTPROTO=none ONBOOT="yes" IPADDR=192.168.0.95 NETMASK=255.255.255.0 GATEWAY=192.168.0.1 DNS1="192.168.0.1" PEERDNS="yes" TYPE="Bridge" DELAY=0 STP=off USERCTL=no IPV6INIT=no NM_CONTROLLED=no 4 - /etc/init.d/network restart 5 - choose Host device eth0 (Bridge 'br0') in the VM-manager GUI for the virtual-machine's NIC 6 - restart the virtual machines That made it all work. So what I had wrong initially were settings in the ifcfg-xxx files. There are different settings that may work and I just tried some of the not-working combinations. Cheers, Koos. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20130926/00e3755c/attachment-0005.html>