[CentOS-virt] Upgrade of CentOS and libvirt: need help on configuring network

Mon Sep 23 14:52:09 UTC 2013
Stefano Stabellini <stefano.stabellini at eu.citrix.com>

On Mon, 23 Sep 2013, Schut, Koos J J (Koos) wrote:
> 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?

Did you try to follow:

http://wiki.xen.org/wiki/Host_Configuration/Networking

?