Fwd: Received route with strange next-hop

[Christian Kölpin]

Am 17.04.2012 12:28, schrieb Ondrej Zajicek:
> On Mon, Apr 16, 2012 at 10:41:08PM +0200, Christian Kölpin wrote:
>> Hello Community
>>
>> First I have to say, the problem occurs in a lab/soho environment, so it
>> might be unusal to normal bird purposes.
>>
>> I'am running two routers who uses bird/OSPF to exchange their routing
>> tables. One router represents the firewall and "internet-connection",
>> the second runs several VPN daemons (IPSec, OpenVPN, L2TP). Some foreign
>> Routers are connected via these VPNs and running OSPF as well (mix
>> quagga/bird). All is running well except some "stange next-hop"
>> messages. The Problem is, I don't understand why i get these messages.
>> To me, the routes looks ok. So I don't understand the problem at all.
>> Maybe someone can help me to understand it.
>>
>> OS: linux/openwrt
>> Bird: version 1.3.3
>>
>> I have two "problematic" routes who leads to "strange next-hop" messages:
>> 1) network: 192.168.100.128 gateway 192.168.100.130 netmask
>> 255.255.255.128 (/25)
>> bird-message: KRT: Received route 192.168.100.128/25 with strange
>> next-hop 192.168.100.130
>> add info: the network is a OpenVPN "Roadwarrior"-network. There is a
>> tun0-ptp-interface with 192.168.100.129 as local an 192.168.100.130 as
>> foreign address
>>
>> 2) network 0.0.0.0 (default) gateway 84.57.128.1 netmask 0.0.0.0
>> bird-message: KRT: Received route 0.0.0.0/0 with strange next-hop
>> 84.57.128.1
>> add info: the default route is injected by the pppd when the router
>> connects to my german-isp via pppoe (DSL). I have a ptp-interface with
>> my dynamic ip an the GW-address as foreign address
>>
>> Both gateways are listed in the kernel-routing as directly connected via
>> a /32 route (eg 84.57.128.1 gw 0.0.0.0 netmask 255.255.255.255)
> Hello
>
> BIRD generally assumes tha that gateway of routes is a direct neighbor
> according to IP addresses on interfaces, not according to routing tables.
> So having /32 device route does not help. But you could add ptp address
> on that iface:
>
> ip addr add a.b.c.d peer 84.57.128.1 dev XXX
> (where a.b.c.d is the current local IP of that device
Hello

pppd and openvpn does add this address already. If i run this command
the message "RTNETLINK answers: File exists" appears.
So i assumed the peer 84.57.128.1 should known as "directly connected".

ifconfig output:
tun0      Link encap:UNSPEC  HWaddr
00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 
          inet addr:192.168.100.129  P-t-P:192.168.100.130 
Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1

pppoe-wan Link encap:Point-to-Point Protocol 
          inet addr:84.57.179.177  P-t-P:84.57.128.1  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1492  Metric:1

ip route output
192.168.100.130 dev tun0  proto kernel  scope link  src 192.168.100.129
84.57.128.1 dev pppoe-wan  proto kernel  scope link  src 84.57.179.177

Yeah the ultimate solution is ... a ultimative ;) but till i start
ignoring Error-Messages i try to find out why it appears.

greetings
Raptor 2101