Ubuntu Server 12.04.1 and Linux KVM on Fujitsu RX300 S5

[Thorsten Göllner]

We use a very similair setup. I had the same problem. "My" solution was 
to allow forward ip traffic on the host's firewall:

iptables -A FORWARD -i br0 -d {ip address of the guest} -j ACCEPT

I do not really know, why this is neccessary, but it works (for me). 
Give it a try.

Am 27.08.2012 16:52, schrieb S`row-Lain:
> Hello List,
>
> we are running VMs in KVM on different Servers and everything is fine.
> Now I wanted to set it up on Fujitsu RX300 S5 Servers, but using bridged
> networking, all packets are dropped but to the host...
>
> To explain it in more detail:
> I install 12.04.1 Server AMD64 with default settings. Afterwards I update
> the server with aptitude and set up the network like this:
>
> auto br0
> iface br0 inet static
>         address 192.168....
>         netmask 255.255.255.0
>         network 192.168....
>         broadcast 192.168....
>         gateway 192.168....
>         # dns-* options are implemented by the resolvconf package, if 
> installed
>         dns-nameservers ...
>         dns-search intel.local
>         bridge_ports    eth0
>         bridge_stp      off
>         bridge_maxwait  0
>         bridge_fd       0
>
> Network connection is fine for the Host. On other Hardware this setup 
> runs smoothly on
> Ubuntu Server 11.04 since more than a year...
> If I setup a VM Guest (1204 Server) connected via a bridge (br0), the 
> guest can only reach
> the Host. All other packets seem to be dropped. If I use a NAT-NIC 
> (default), the network
> connection is fine.
>
> I use virtio-drivers and the Server Hardware are two Fujitsu RX300 S5. 
> Doesn't work on both
> systems. I compared iptables-rules, route-entries, all identical to 
> the other servers, where it
> works just fine.
> Does anybody have an idea, what it could be? I am really stuck =(
> Do you need more info?
>
> root at in3db:~# brctl show
> bridge name    bridge id        STP enabled    interfaces
> br0        8000.001999734942    no        eth0
>                             vnet0
> virbr0        8000.000000000000    yes
> ---
> root at in3db:~# lspci | grep Ethernet
> 08:00.0 Ethernet controller: Intel Corporation 82575EB Gigabit Network 
> Connection (rev 02)
> 08:00.1 Ethernet controller: Intel Corporation 82575EB Gigabit Network 
> Connection (rev 02)
>
> Cheers
> Michael H.