[fedora-virt] Network configuration for qemu+kvm

[Gene Czarcinski <gene czarc net>]

On Sunday 16 August 2009 23:35:07 Dale Bewley wrote:
> http://www.libvirt.org/formatdomain.html#elementsNICS
> http://wiki.libvirt.org/page/Networking#Fedora.2FRHEL_Bridging

Dale ... first, I want to thank you for providing these URLs as this is the 
type of information I have been looking for.

I do not usually like changing the subject for a reply but I am taking this 
thread in a somewhat different direction.

Here are some questions for anyone on this mailing list:

1. Is the documentation cited in the above URLs currently valid for Fedora 11 
and Fedora 11 + preview?  Virtualization on Fedora is a fast moving work in 
progress.  Thus, documentation does not usually keep up with the reality of 
the code.  If there are differences, can someone point me to documentation 
about these differences.

2.  I am a recent convert to qemu-kvm from VMware.  While the NAT NIC 
interface should work for some of my needs, I would also like something 
similar to VMware's "bridged" NIC so that the guest looks just like another 
system on my local network.

While the documentation from the above URLs is useful, I also found some 
possible contradictions where I need some clarification.

3.  Looking at http://wiki.libvirt.org/page/Networking#Fedora.2FRHEL_Bridging 
I conclude that to get bridged networking I will need a separate bridge device 
for every guest that could run concurrently.  While this could be done, it is 
also a bit of a pain to keep track of which guest is using which bridged 
interface.

4.  After noodling around the two documentation web sites I found: 
http://www.libvirt.org/formatnetwork.html#examples which implies that I can 
set up additional interfaces similar to the NAT interface ... one as a routed 
(bridged) interface and a second type for an isolated network ("host-only") 
interface.  Furthermore, the implication is that guests can share the virbr0, 
virbr1, and virbr2 interfaces.  I sure hope this works because it is precisely 
what I am looking for.

Suggestions, pointers to additional documentation and any other comments are 
appreciated.

BTW, if the virbr0, virbr1, virbr2 stuff does work as implied in 
http://www.libvirt.org/formatnetwork.html#examples then I suggest that these 
definitions should be added to the default.xml definition for networks ... not 
necessarily all autostarted but certainly defined.

Gene