[Olsr-users] Problems with the quagga plugin

Damien Miliche (spam-protected)
Tue May 17 11:59:55 CEST 2011

Hi Vasilis,

Thanks for your answer. Anyway, I am not sure to understand the "recursive
routes" problem :s

> This happens because Quagga considers nexthops which are recursively
> reachable 
> as inactive. I beleive this assumption is correct with classic subneted 
> routing but fails in MANETs. Since olsrd-quagga plugin is attempting to
> bring 
> these two "worlds" in contact, we have to find a solution which breaks
> of 
> them.
> One solution is to treat host routes the same way as directly connected
> routes 
> which are always considered valid nexthops. But this would mean more
> modifications which I'd prefer to avoid. AFAIK, Quagga makes an exception
> on 
> the de-activation of recursive routes in iBGP networks. Maybe we could
> the 
> same mechanism to "activate" OLSR routes.

To give a better view of my problem, here is what I get on a gateway node
( on wlan0, on eth0) that sees (at least
suppose to see) two direct olsr/MANET neighbours ( and, and an indirect one ( via, and is connected through Ethernet to an OSPF-enabled host

from the httpinfo olsrd plugin:
    OLSR Routes in Kernel
    Destination		Gateway		Metric	Cost (ETT)	Interface	1	4392.000	wlan0	1	4427.000	wlan0	2	18341.000	wlan0
what is OK according to my topology, and what I would like to redistribute
to the OSPF node.

from zebra:
    Router> sho ip route
    Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF,
           I - ISIS, B - BGP, H - HSLS, o - OLSR, b - BATMAN,
           > - selected route, * - FIB route

    C>* is directly connected, lo
    K>* is directly connected, eth0
    C>* is directly connected, wlan0
    o>* [125/1] is directly connected, wlan0, 00:01:06
    o>* [125/1] is directly connected, wlan0, 00:18:23
    o [125/2] via inactive, 00:00:24
    O [110/10] is directly connected, eth0, 00:27:36
    C>* is directly connected, eth0

the resulting Kernel routing table:
    # route -n
    Kernel IP routing table
    Destination     Gateway         Genmask         Flags Metric Ref    Use
Iface UH    1      0        0
wlan0 UH    1      0        0
wlan0   U     1      0        0
eth0     U     1000   0        0

To get that, I deactivated the "quagga bug workaround" for entries where
destination = gateway in the quagga plugin for olsrd.
The difference with when this workaround is activated, is that the first
two entries are then not added to the kernel routing table because marked
as inactive in zebra.

As, without the workaround, the gateway node ( is not
inactive, I don't understand why the route towards is still
marked as inactive.
Moreover, as you can see, the valid/active host routes are already marked
as "directly connected", then should also be considered as valid nexthops.

Best regards,

Damien Miliche

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