[ILUG] Xen bridging problem

[Tor Bendiksen]

On Thu, Feb 08, 2007 at 03:27:15PM +0000, Niall O Broin wrote:
> I have a couple of servers at Hetzner running Xen. In each case, the  
> dom0 has one public IP, and I have also been allocated a /29 from  
> Hetzner, from which I have 5 available IPs. These addresses are  
> routed to the respective servers, on which I have Xen VMs running  
> which each use one of the IPs.
> 
> This works just as I expect it to on both servers, with packets  
> addressed to one of the IPs from the /29 landing on the eth0  
> interface, and being transferred by Xen bridging to the relevant VM.
> 
> However, I have another server at a different provider, with the same  
> IP allocation i.e. 1 + 8, and it runs the same OS as the Hetzner  
> servers i.e. Debian etch with kernel 2.6.18-1-xen-k7, which is up to  
> date.
> 
> The problem with the other provider's box is that networking doesn't  
> work correctly - the domUs can't ping their default routes. Again,  
> the configuration of a working domU appears to be the same as that of  
> a non-working one. Networking has been setup correctly the provider  
> because if I add one of the public IPs to eth0 on the dom0, I can  
> acces that IP from the world.
> 
> I'm stumped - any ideas?

I have no solution, but when I set up a server at Hetzner (same setup) I
had simmilar or same problem. I was completely stumped. Whatever I did I
could not get it to work. 

I went through loads of different howto's and documentation, but to no
avail. 

Eventualliy, after having messed around that much that I have probably 8
different kernels I decided to start from scratch. 

I believe I did the same thing as I did the first time around, except
this time it actually worked. 

I don't have my notes here at the moment, and since I didn't actually
find the root cause I don't expect them to help much anyway..

Sorry I can't be more helpful. But perhaps if you do find the problem, 
at least *I* can have some piece of mind :-)

Do let me know how you get on.

> Niall
> 

-- 
Tor