Fix for routing table breaking bug

[Martin Kraus]

On Fri, Oct 24, 2008 at 11:05:45PM +0200, Ondrej Zajicek wrote:
> Hello
> 
> Here is a patch fixing a bug that causes breakage of a local routing
> table during shutdown of Bird. The problem was caused by shutdown
> of 'device' protocol before shutdown of 'kernel' protocol.  When
> 'device' protocol went down, the route (with local network prefix)
> from different protocol (BGP or OSPF) became preferred and installed
> to the kernel routing table. Such routes were broken (like
> 192.168.1.0/24 via 192.168.1.2). I think it is also the cause
> of problem reported by Martin Kraus.
> 
> The patch disables updating of kernel routing table during shutdown of
> Bird. I am not sure whether this is the best way to fix it, I would
> prefer to forbid 'kernel' protocol to overwrite routes with
> 'proto kernel'.
> 
> The patch also fixes a problem that during shutdown sometimes routes
> created by Bird remained in the kernel routing table.

beautiful:)
martin