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Re: [Xen-users] Network configuration problem

Hi again,

first, I have to admit that english is not my native language, so I am having a
hard time to describe such things. I will try to explain it a bit better.

>So the guest is pingable from the outside, but can't ping to the
>outside and get replies back?
I can ping the IP addresses, yes. I can not ping anything from inside the guest.

>At first glance, I see all the aliases you give for eth2:X and don't
>understand, what this is good for. I see you try to assign your
>different network segments, but I don't understand why and what for.
Perhaps I am lacking some knowledge in configuring network interfaces here?
I wanted to have my network card eth2 listen to the providers IP and to
the two aliases. Since I am quite new to this, I might have choosen the wrong

>Another important question: do you want to use bridged, nat or routed
>networking? For what kind of virtual setup are you heading here - can
>you give us a big picture of the whole network?
That's what I am not sure off. I'll try a little picture.

                                 eth2  (( dom0 ))

             eth2:1                                     eth2:2
     (( used to host a small webserver ))     (( hosting a mail server ))

Now I wanted the dom0 system to redirect all packages for the IP of eth2:1
to the matching XEN guest, same for eth2:2.

Again, I am new to all this, so I'm not aware, which method is the right one for
me to use in such a case.

If that's just the wrong method to set things up, what's right? Any help is very
much appreciated. Feeling totally stupid on this one.

> I also don't understand why you don't have an eth0 or eth1. Can you
>explain your hardware setup?
There is a eth0 and eth1 network interface available, but these are only used
for local networks, eth0 is connected to a backup host, eth1 is connected to my
private network.

>Look at brctl  show if all interfaces are connected to bridges correctly.
So I ran xm create for the first guest, and after starting it, brctrl show gives

bridge name     bridge id               STP enabled     interfaces
xenbr2          8000.feffffffffff       no              vif1.0

Now I checked if vif1.0 is really attached to my guest, and xm network-list for
the domain shows

Idx BE     MAC Addr.     handle state evt-ch tx-/rx-ring-ref BE-path
0   0  00:16:3e:43:34:ed    0     4      8     522  /523     

If I am not totally stupid, this tells me, the virtual network interface of
my guest, is attached to xenbr2, which in turn is the bridge for eth2.

>3) when you hook your different subnet into one pohysical bridge
>(which is strrange and I donät see the reason what this should bring),
I'm not really sure, how to do this right. But I probably lack knowledge on
network setups in this case.

I would have to add routes in the dom0 for the guests, right?

With kind regards,

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