[Olsr-users] OLSR mesh with loop potential... having problems.

[Vigneswaran R]

On Sunday 07 October 2012 12:53 AM, Markus Kittenberger wrote:
> On Fri, Oct 5, 2012 at 7:14 AM, Vigneswaran R <(spam-protected) 
> <mailto:(spam-protected)>> wrote:
>
>     Dear all,
>
>     Recently we also noticed loops in the routes established by
>     OLSRv1, on a partial mesh topology (with ~20 machines). We are
>     using olsr 0.6.3 with default configuration file and only
>     Interface line has updated. Not using any plugins. As of now wired
>     connections and at the deployment will be using wireless radios.
>
>     Due to the loop, the packets sent through one Interface and
>     received on another.
>
> you mean return packets just took another route as the packets towards?

Yes, exactly.

> this is normal, and you need e.g just 4 nodes with all having 2 
> etx-1.0 links, aligned in a square, to have a 50% chance to get this, 
> and imho there is nothing wrong about this,..

Ok. Thank you for the clarification.


Regards,
Vignesh

>
> Markus
>
>     ssh, ping worked fine regardless of that. However, we realized the
>     loop when 'nmap' erroneously reported a node as down.
>
>     One point to note here is, when we conducted the test we used
>     10.0.0.0/8 <http://10.0.0.0/8> subnet for all the nodes, so that
>     we can do random reconnects to simulate node movements. However,
>     Henning suggested to put different Interfaces of the same router
>     into different subnets (in his reply on another thread). So, when
>     we do the tests again we will see whether that has any impact on
>     loops.
>
>     However, whether loop in routes are expected in general, for such
>     topologies? or by doing some configuration changes can we avoid that?
>
>     Thank you.
>
>
>     Regards,
>     Vignesh
>
>
>
>
>     On Wednesday 27 June 2012 03:24 AM, Érico Porto wrote:
>>     I think he meant a file containing the following lines
>>
>>     IpVersion 4
>>     Interface "wlan0"
>>     {
>>     }
>>
>>     Érico V. Porto
>>
>>
>>     On Tue, Jun 26, 2012 at 4:27 PM, John Clark <(spam-protected)
>>     <mailto:(spam-protected)>> wrote:
>>
>>
>>         On Jun 26, 2012, at 12:06 PM, Markus Kittenberger wrote:
>>
>>>
>>>         On Tue, Jun 26, 2012 at 8:29 PM, John Clark
>>>         <(spam-protected) <mailto:(spam-protected)>> wrote:
>>>
>>>             Thanks all,
>>>
>>>             I updated my olsrd to the 6.3 version that's on the
>>>             download page. Compiled ok, and did an install and
>>>             'install_libs', which seems to have cured my problem
>>>             with loading the plugins.
>>>
>>>         (you could have done an install_all)
>>>
>>>
>>>             I used the default installed olsrd.conf, and only
>>>             changed the interfaces list.
>>>
>>>         try to use a new olsrd.conf (i.e an absolutely empty one
>>>         except the protcol version ipv4 or ipv6 and the interface names)
>>
>>         I believe I'm using that conf, all I changed was the
>>         interface list.
>>
>>         I'll recheck that...
>>
>>>
>>>         this will use default settings for everything, and might
>>>         cure your actual problems,..
>>>
>>>             As a note, in the past, upon reflection, my 'meshes'
>>>             have been either linear chains or trees, and there have
>>>             bee no internal loops.
>>>
>>>
>>>         olsrd works on such topologies, as infact such topologies
>>>         are what it is meant to operate on.
>>>         (it definetely does not need the networks to be a tree,..)
>>
>>         I've been working on this more, and will try to give more
>>         details as they come to me, but at the moment, I have the
>>         problem when the one link is removed, problems arise.
>>
>>
>>         Thanks,
>>         John Clark.
>>
>>
>>         --
>>         Olsr-users mailing list
>>         (spam-protected) <mailto:(spam-protected)>
>>         https://lists.olsr.org/mailman/listinfo/olsr-users
>>
>>
>>
>>
>
>
>     --
>     Olsr-users mailing list
>     (spam-protected) <mailto:(spam-protected)>
>     https://lists.olsr.org/mailman/listinfo/olsr-users
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.olsr.org/pipermail/olsr-users/attachments/20121008/be44ad76/attachment.html>