[Olsr-users] Multi-hop OLSR

[Markus Kittenberger]

On Thu, Oct 11, 2012 at 11:33 PM, Ricardo T. Macedo
<(spam-protected)>wrote:

> Hi Song,
>
> Thank you for the suggestion. I will try to create a blocking with
> iptables, when I have the results I will communicate.
>
It will very likely not change anything, as in your first mail/screenshot
olsrd was already doing multi-hop (or it very likely did this, as it
reported one 2hop neighbour and one direct neighbour)

So, the problem is very likely that "something" in your networking
setup/configuration stops it from working.

i.e. the best to verify this, is is to remove/stop olsrd from your setup,
and just setup static routing.

If this does work, only than its time to look for olsrd problems.

i.e. on node N1:
ip route add N2 dev wlan0
ip route add N3 via N2 dev wlan0
echo 0 > /proc/sys/net/ipv4/conf/wlan0/rp_filter

on N2:
ip route add N1 dev wlan0
ip route add N3 dev wlan0
echo 1 > /proc/sys/net/ipv4/ip_forward
echo 0 > /proc/sys/net/ipv4/conf/wlan0/rp_filter

on N3:
ip route add N2 dev wlan0
ip route add N1 via N2 dev wlan0
echo 0 > /proc/sys/net/ipv4/conf/wlan0/rp_filter

Replace N1-3 with the IP-adresses of the nodes wireless interfaces.
And use something else than wlan0 if your wifi interface has a different
name.

Now N1 and N3 should be able to ping each other.
(unless firewall, or whatever things, conflict)

Markus

>
> Best regards,
> Ricardo.
>
> On Thu, Oct 11, 2012 at 6:07 PM, Song Gao <(spam-protected)> wrote:
>
>> Hi Ricardo,
>>
>> Multiple hops are done by OLSRd automatically. It might because all of
>> your wireless devices are placed close to each other. If OLSRd sense they
>> are reachable, it won't set up multiple hops.
>>
>> You can either use iptables to block certain nodes based on mac address,
>> or place your laptops far from each other. If, e.g., placed like this:
>> A ---- B ---- C
>> , where A and B can communicate, B and C can communicate, but A and C
>> cannot hear from each other, then OLSRd will definitely set multi-hops for
>> you.
>>
>> You can use "ip route" to get the routing table, or use traceroute
>> command to get hops on each node.
>>
>> --
>> Song Gao
>> http://song.gao.io/
>>
>> On Thursday, October 11, 2012 at 3:47 PM, Ricardo T. Macedo wrote:
>>
>> Hi Song,
>>
>>    Thanks for your help, but I would like to know how to enable the
>> multi-hop (just like in http://www.olsr.org/docs/report_html/node27.html
>> ).
>>
>> Do you have any idea how I can enable this functionality?
>>
>> Best regards,
>> Ricardo.
>>
>> On Thu, Oct 11, 2012 at 5:28 PM, Song Gao <(spam-protected)>wrote:
>>
>> It's possible to use block certain node at link layer by using
>> iptables with --mac option. Check this page out:
>> http://www.cyberciti.biz/tips/iptables-mac-address-filtering.html
>>
>> By blocking certain nodes from one node based on mac address, OLSRd
>> control messages are also blocked, as a result, OLSRd would consider
>> the blocked nodes not reachable, and build multi-hop routing tables.
>>
>> Kind regards,
>> --
>> Song Gao
>> http://song.gao.io/
>>
>> On Thu, Oct 11, 2012 at 3:09 PM, Ben West <(spam-protected)> wrote:
>> > How are the laptops actually building the connections w/ each other?
>>  I.e.
>> > over their wifi adapters, or over a wired LAN?
>> >
>> > Also, how are you ensuring the route N1 -> N2 -> N3?  If the laptops are
>> > meshing wirelessly, it may be difficult to ensure OLSR actually choses
>> your
>> > desired route, due to transient fluctuations in wifi signal quality.
>> >
>> > If you are not already doing so, I would recommend using the
>> LinkQualityMult
>> > parameter on each node specify negative biases for the node(s) you do
>> not
>> > want to be that node's next hop.
>> >
>> > On Thu, Oct 11, 2012 at 9:36 PM, Ricardo T. Macedo <
>> (spam-protected)>
>> > wrote:
>> >>
>> >> Hello,
>> >>
>> >> I've been working with OLSR protocol and I want to reproduce a scenario
>> >> with multi-hops. I'm using iperf to generate traffic data packet in the
>> >> network.
>> >> In my tests, I'm using three notebooks with backtrack linux (backtrack
>> 5
>> >> R2). Every notebook (nodes), I labeled by N1, N2 or N3. N1 can
>> communicate
>> >> with N3 only through N2, in multiple hop way. Every node is running
>> OLSR
>> >> protocol. I try to run the iperf as a server in N1 ($ iperf -u -s -p
>> 5000).
>> >> In N3, I run the iperf as a client ($ iperf -u -c <IP_address_N1> -p
>> 5000).
>> >> In the node N3, I just run the OLSR protocol. In a single hop, I have
>> no
>> >> problem, but in multi-hop it doesn't work. OLSR is finding the
>> multi-hop
>> >> correctly, but when I try to send the data packet I get the "WARNING:
>> did
>> >> not receive ack of last datagram after 10 tries" error.
>> >>
>> >> Does anyone have any idea about what could be wrong?
>> >>
>> >> Thanks,
>> >> Ricardo
>> >>
>> >> --
>> >> Olsr-users mailing list
>> >> (spam-protected)
>> >> https://lists.olsr.org/mailman/listinfo/olsr-users
>> >
>> >
>> >
>> >
>> > --
>> > Ben West
>> > (spam-protected)
>> >
>> >
>> > --
>> > Olsr-users mailing list
>> > (spam-protected)
>> > https://lists.olsr.org/mailman/listinfo/olsr-users
>>
>>
>>
>>
>
> --
> Olsr-users mailing list
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