[Olsr-users] Routing problem with bad ETX

[Ferry Huberts]

On 30/04/13 18:04, Saverio Proto wrote:
> You need to adjust your multicast rate.
> Btw 0.6.3 olsrd is very old. Please use this feed to compile latest version:
> 
> https://github.com/openwrt-routing/packages

Saverio, can you upgrade this feed to 0.6.5.3?
Thanks!

> 
> best regards
> 
> Saverio Proto
> 
> 
> 2013/4/30 Simon Ebnicher <(spam-protected)>:
>> Hi,
>> we have set up a small OLSR mesh network with three routers (TP-Link
>> TL-WDR3600 running OpenWrt 12.09rc1, olsrd 0.6.3). We placed two routers
>> near to each other, and the third router at quite some distance.
>> R1 <----ETX:~1----> R2 <---------------ETX: 1.x to 2.x-----------> R3
>>
>> The ETX on the direct link between R1 and R3 is usually below 2 (about
>> 1.3 to 1.7), so the direct route is preferred. However, the direct route
>> is completely unusable for data transfer (e.g., ping reports >95% packet
>> loss). As soon as two hop route via R2 is used, ping and other traffic
>> works fine.
>> We are wondering why the unreliable link is rated too optimistically. We
>> suspect that the Hello and TC multicast packets (which are used to
>> calculate the ETX) may have a better reception probability than unicast
>> packets (e.g., because they are sent at lower rates, no RTS/CTS). This
>> would lead to ETX values that do not reflect the link accurately.
>>
>> Can anyone confirm or explain this behaviour and maybe offer a solution?
>>
>> Best regards,
>> Simon Ebnicher
>>
>> --
>> Olsr-users mailing list
>> (spam-protected)
>> https://lists.olsr.org/mailman/listinfo/olsr-users
> 

-- 
Ferry Huberts