On Mon, Oct 29, 2007 at 01:40:07PM -0700, Aaron Glenn wrote:

quoted text
> running 4.2/i386 as of two weeks ago, I've got a default route that

> isn't being seen as valid and consequently not installed in the RIB.

> when I first rolled this router out, however, it was valid and being

> installed. while I'm interested in what could have happened between

> then and now, I'm more interested in how the RDE actually makes its

> decisions on validity. I see no obvious reason for this route to be

> not valid.

>

> everything else (demotion, 'prefix lists', etc) works great, however (-:

>

> relevant info:

>

> root@edge-rtr-2$ bgpctl show rib nei 38.103.65.50 in

> flags: * = Valid, > = Selected, I = via IBGP, A = Announced

> origin: i = IGP, e = EGP, ? = Incomplete

>

> flags destination         gateway          lpref   med aspath origin

>       0.0.0.0/0           38.103.65.50       100     0 174 i

>

> I am learning that nexthop from another session with 174:

>

> root@edge-rtr-2$ bgpctl show fib bgp

> flags: * = valid, B = BGP, C = Connected, S = Static

>        N = BGP Nexthop reachable via this route

>        r = reject route, b = blackhole route

>

> flags destination          gateway

> *B    38.103.65.50/32      38.104.XXX.37

>

> root@edge-rtr-2$ cat /etc/bgpd.conf

> AS 10XX0

> router-id 72.37.XXX.178

>

> network inet connected

> network inet static

> network 38.98.XXX.0/24

>

> neighbor 72.37.XXX.177 {

>         remote-as 10XX0

>         announce all

> }

>

> group "COGENT" {

>         remote-as 174

>         depend on bge1

>         softreconfig in yes

>         softreconfig out yes

>         neighbor 38.104.XXX.37 {

>                 local-address 38.104.XXX.38

>                 set prepend-self 3

>                 announce self

>         }

>         neighbor 38.103.XXX.50 {

>                 announce none

>                 multihop 8

>         }

> }

>

> 

The nexthop depends on a bgp route which is considered evil and therefor

not allowed by default. Add "nexthop qualify via bgp" to the global config

part and your setup should work again.
--

:wq Claudio