[libvirt] Network Configuration question

[Hugh O. Brock]

On Sun, Feb 08, 2009 at 10:34:06PM +0100, Remko Nolten wrote:
> Hi!
>
> For a shared virtual hosting project with some friends we need a pretty 
> specialized network configuration. Because we have virtually no time for 
> experimenting (no pun intended), and the hosting organization has no 
> experience with libvirt/KVM configurations they suggested to try and ask 
> here.
>
> So, this is the situation: We have a server with one physical  
> connection. Each user gets one virtual machine with its own IP-address  
> (we have our own ip-range). The hosting organization gives us one "main" 
> address 'A' with netmask 255.255.255.0 (/24) and a default gateway for 
> our host machine. Besides this we get a number of addresses B1, B2, etc. 
> with netmask 255.255.255.255 (/32) and without a default gateway. The 
> switch just routes the traffic to our server for each ip-address we own 
> (A and Bn).
>
> According to our hosting organization, the normal solution is to  
> configure a loopback interface for each of the ip-addresses on the  
> server so you can configure your software just to use one of the  
> addresses. But we are not sure how this will work out in our virtual  
> environment. Our intuition tells us we need to use the routing network  
> forwarding mode, but when we bring the server to the data center we  
> don't want to have any surprises. :)

Hi there.

This actually sounds like a fairly standard configuration. What you
want to do is set the single NIC on your server to bridge, following
the instructions at
http://wiki.libvirt.org/page/Networking#Bridged_networking_.28aka_.22shared_physical_device.22.29
. Each VM can then have its own IP, which in your case sounds like it
will be static. 

Hope this helps,
--Hugh

>
> Here at home I don't have to possibility to create similar circumstances 
> as in the data center due to some restriction from my ISP, so I hope 
> someone can tell me if our intuition is correct or that we need to use 
> some other method.
>
> Thanks in advance!
>
> -- 
> Remko Nolten
> Tel: 		06-45600767
> E-mail: 	remko at nolten.nu
>
>
>
> --
> Libvir-list mailing list
> Libvir-list at redhat.com
> https://www.redhat.com/mailman/listinfo/libvir-list