[libvirt] [PATCH] network: bridge: Don't start network if it collides with host routing

[Daniel P. Berrange]

On Mon, May 24, 2010 at 12:52:40PM +0100, Neil Wilson wrote:
> You need to be very careful not to hit a valid use case here.
> 
> RFC3069 provides for a mechanism whereby a supernet/subnet system is
> setup to allow better use of available IPv4 address space. This is
> becoming of increasing concern as IPv4 space exhausts.
> 
> To implement this you turn on Proxy ARP on a host and inject /32
> routes advertised from other hosts into the routing table. The network
> on the current host has a wide subnet mask (for example 10.0.0.0/8),
> so that the host responds to ARPs for VM guests that are actually on a
> completely different host.

The current network code only supports NAT, or a separate
routed subnet & thus currently require a non-clashing subnet. 
Proxy ARP is a future RFE, so not a problem wrt this patchset
currently.


Daniel
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