[Fedora-xen] xen networking

[Dale Bewley]

Wow, I didn't even know that /etc/libvirt/qemu/networks/ existed. Now I know how to remove that annoying 192.168 network. Thanks :)

I'm on F7 and not doing any bonding, but I am using bridges on VLANs and I setup all my interfaces and do my filtering the old fashioned way in /etc/sysconfig. 

Sorry if I'm stating the obvious below...

[root at helix sysconfig]# grep forward /etc/sysctl.conf
# Controls IP packet forwarding
net.ipv4.ip_forward = 1

[root at helix sysconfig]# grep phys iptables
-A FORWARD -m physdev  --physdev-is-bridged -j ACCEPT

[root at helix network-scripts]# cat ifcfg-eth0
DEVICE=eth0
MTU=1504
BOOTPROTO=none
ONBOOT=yes
BRIDGE=br101

[root at helix network-scripts]# cat ifcfg-vlan6
DEVICE=eth0.6
BRIDGE=br6
VLAN=yes
MTU=1500
ONBOOT=yes
BOOTPROTO=none

[root at helix network-scripts]# cat ifcfg-br6
DEVICE=br6
TYPE=Bridge
BOOTPROTO=static
ONBOOT=yes
MTU=1500
IPADDR=1.1.1.1
NETMASK=255.255.255.0
NETWORK=1.1.1.0
BROADCAST=1.1.1.255

And set (network-script /bin/true) in xend-config.sxp.
Change your domU bridge like so:

# virsh shutdown <imgname>
# virsh dumpxml <imgname> | sed s/br101/br6/ > <imgname>.xml
# virsh define <imgname>.xml
# virsh startup <imgname>

--
Dale Bewley - Unix Administrator - Shields Library - UC Davis
GPG: 0xB098A0F3 0D5A 9AEB 43F4 F84C 7EFD  1753 064D 2583 B098 A0F3

----- "Mark Nielsen" <mnielsen at redhat.com> wrote:
> Since I have not yet been able to resolve my complex networking issues
> 
> in RHEL 5, I decided to upgrade 1 of my cluster nodes to 5.1 beta and
> 
> take this new libvirt networking for a spin. I'm not sure if this is 
> going to make my issue easier to resolve, or add to the complexity so
> 
> I'm writing this e-mail to hopefully get some suggestions as how to 
> proceed.
> 
> My network looks like this:
> eth2 & eth3 comprise bond1
> bond1 has bond1.48 - my public VLAN interface with an IP for dom0
> bond1 has bond1.20 - my VLAN for some domU systems, dom0 has no IP on
> 
> this VLAN
> bond1 has bond1.21 - my VLAN for some domU systems, dom0 has no IP on
> 
> this VLAN
> 
> I want to bridge to bond1.20 from some domU systems, and bond1.21 from
> 
> other domU systems. dom0 should not have an IP on these VLANs.
> 
> 1) do I need to define a network interface in 
> /etc/libvirt/qemu/networks/ for each VLAN? (bond1.20 and bond1.21)
>  1a) If yes, do I need to have an IP address  for the bond1.20 and 
> bond1.21 interface defined in 
> /etc/sysconfig/network-scripts/ifcfg-bond1.20 and bond1.21?
>  1b) Do I also need to define an IP address on that VLAN in the .xml 
> file for that network?
> 
> or
> 
> 2) Can I just have 1 default.xml network and then use iptables to 
> forward to a specific VLAN based on bond1.20 and bond1.21 configured
> in 
> /etc/sysconfig/network-scripts/ ??
> 
> #2 would be best, if possible. Unfortunately there's not a lot of 
> documentation out on the new networking methods. I've read 
> http://watzmann.net/blog/index.php/2007/04/27/networking_with_kvm_and_libvirt
> 
> but that doesn't get in to all the VLANs and bonds.
> 
> Any help is greatly appreciated!