Re: Bridges

[Jonathan Tripathy <jonnyt@abpni.co.uk>]

On 20/08/10 09:53, Pascal Hambourg wrote:
> Jonathan Tripathy a écrit :
>    
>>>>>>>> However, in the /proc/sys/net/ipv4/conf folder, I
>>>>>>>> don't see my "public" bridge, only the private one. Incidently, the
>>>>>>>> private one is the only bridge in my system that has an IP address
>>>>>>>> asigned to it...
>>>>>>>>
>>>>>>>>                  
>>>>>>> Ok. May I ask what is your kernel version ? Older than 2.6.21 ?
>>>>>>>
>>>>>>>                
>>>>>> Linux xx.xx.xx.xx 2.6.18-194.8.1.el5xen #1 SMP Thu Jul 1 19:41:05 EDT
>>>>>> 2010 x86_64 x86_64 x86_64 GNU/Linux
>>>>>>
>>>>>>              
>>>>> As I expected. A change occured in 2.6.21, recent kernels automatically
>>>>> link interfaces to the IP stack.
>>>>>
>>>>>            
>>>> So in my case, am I at a disadvantage
>>>>
>>>>          
>>> On the contrary, the old behaviour is an advantage if you don't want an
>>> interface to participate in IP operation.
>>>        
>> Excellent! If I were to upgrade at a later date, is it just a matter of
>> making sure that everything returns 0 in the above files?
>>      
> Setting net.ipv4.conf.<interface>.forwarding=0 will disable forwarding
> of IP packets received on<interface>. But I'm afraid it won't disable
> all IP operation on it (ARP resolution, accept IP packets for local
> delivery...)
>    

Just out of interest, if routing was enabled on the Dom0, how would the 
guests be able to use it, if the bridge that they were connected to 
didn't have an IP address? Assuming that all IPs for the other 
interfaces on the Dom0 were on a different subnet..

Thanks