Re: [Xen-users] NAT on 3.0.2?

["John Wells" <jb@xxxxxxxxxxxxxxxxxxxxx>]

Tom Brown said:
>> What exactly is not working?
>
> He seems to be at the same spot (or close) to where I was at...
>
> http://lists.xensource.com/archives/html/xen-users/2006-07/msg00368.html
>
> you can see packets leaving the domU, getting NAT'd by the dom0, going out
> to an external box, being echoed back...
>
> And here is where I run into trouble. I remember seeing the return packets
> on peth0 and not eth0 as John describes, but that means I still had a
> bridging config alive... and _that_ seems to trigger the kernel
> issue?/bug? which produces an error message
>
>   "Performing cross-bridge DNAT requires IP forwarding to be enabled"

Yes. Even though I was getting this message, though, I was able to ping
between domUs...just not outside our LAN. After rebooting and eliminating
the bridge, keeping only NAT'ing in place and using the exact same config,
I could not even ping between domUs. tcpdump'ing on the vifx.x device for
the sending domU displayed the traffic...doing the same on the destination
domU did not.

It appears, after discussing it with many people, that few if any actually
use the built in NAT'ing capability of Xen. Most recommend doing straight
bridging, but then using one of your bridged domUs to do NAT'ing through.
It might be that this approach will work for me, but it'll take some
thinking through.

If you're interested in my config, it mirrored at the time essentially
exactly this: http://www.howtoforge.com/perfect_setup_xen3_debian_p6.

I'm also on Debian Sarge.

Thanks guys.

John


_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users