[CentOS] KVM Setup for Win7 Pro on CentOS 5.x

Sat Aug 18 21:57:27 UTC 2012
Theo Band <theo.band at greenpeak.com>

On 08/18/2012 12:06 AM, Bill Campbell wrote:
> I got things installed yesterday, adding a routed network section
> using virt-manager linked to the private interface, eth1.  I left
> the default NAT interface as-is.
>
> After rebooting the machine, two bridge devices, virbr0 and
> virbr1 appear in 'ifconfig' output with the appropriate IP
> addresses (192.168.122.1 and 192.168.100.1 respectively).
>
> The 'route -n' command shows reasonable routes for the VMs.
>
> I am thoroughly confused by the documentation I've found so far,
> much of which seems to be out of date.
>
> When the Windows VM is active with the network virbr1 defined
> with virt-manager and all other things default, a 'vmnet0' device
> appears in 'ifconfig' output.  I can ping the IPs on the private
> lan (192.168.101.0/24 in this case), but cannot get to the
> outside world, nor can hosts on the LAN ping the VM's assigned IP
> address 192.168.100.114.
>
> If I shut down the VM, manually run 'brctl addif virbr1 eth1', then start
> the VM things change:
>
>     + The IP address assigned to the VM is in the 192.168.101.0/24 block
>       instead of 192.168.100.0/24 defined in virt-manager.
>
>     + I can ping the outside world from the VM.
>
>     + I can ping other hosts in 192.168.101.0/24, but*NOT*  the Linux boxes
>       IP address.
>
>     + I cannot ping anything in 192.168.101.0/24 from the command line on
>       the Linux host (logged in with ssh on the public interface).
>
>     + The command 'brctl show' displays vmnet0 and eth1 vir virbr1.
>
> I'm more than a bit confused at this point.
>
> My main goal is to get LAN and OpenVPN access to the Windows VM.
> I really don't care about Internet access from the Windows VM,
> although Microsoft really wants it to get updates and such.
Do you have iptables enabled? If so add a rule for the bridge as well.