Re: [Shorewall-users] default route(r,s}

[Jerry V. <jv...@sh...>]

Andrew Suffield wrote:
> On Sat, Mar 22, 2008 at 04:22:40PM -0500, Jerry Vonau wrote:
>>>> No, it's looking for preexisting gateways in the main table which were 
>>>> removed with the network scripting.
>>> I don't think so.  As I said in my original post, I have traced and
>>> tracked through the networking scripts and the delete is not being done
>>> in userspace by any of them.  I believe Andrew's explanation that the
>>> kernel is removing the (multi-hop) default route is spot-on.
>>>
>> Doing an "ip addr flush dev DEV" leaves the multi-hop default gateway, 
>> if that interface has one and tags the gateway as dead. Same for 
>> /sbin/ifdown DEV. This is with network cards and not pppd, might be 
>> pppd's code that is causing your headaches.  I'll dig around and see 
>> what I can find for pppd...
> 
> Wrong behaviour. You're looking at removal of the *address*. The
> special thing about ppp connections is that the entire ppp0 interface
> goes away.
> 
> Try rmmodding the driver for your network card driver and see what
> happens. The routing table can accept a default route with an
> incorrect address, but it can't accept a route to a device that
> doesn't exist any more, since that would be a dangling pointer.

Thanks, I see what you mean.... So then I guess the only workaround is 
to use ppp's ip-down to replace the missing gateway.

Jerry