[OLSR-users] WLAN Router with two WLAN interfaces - route flappingissue

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> -----Original Message-----
> From: (spam-protected) 
> [mailto:(spam-protected)] On Behalf Of Rolf Schärer
> Sent: Friday, January 05, 2007 12:41 AM
> To: (spam-protected)
> Subject: [OLSR-users] WLAN Router with two WLAN interfaces - 
> route flappingissue
> 
> Hi group,
> 
> We discovered the following issue running olsr on a WRAP board
> (www.pcengines.ch) with two WLAN interfaces and one Ethernet 
> interface:
> 
> Everything works ok if the other olsr-enabled WLAN routers 
> (mostly Linksys WRT54G's running a Freifunk Firmware) can 
> only connect to one of the WLAN interfaces of the WRAP board. 
> Trouble starts if the other routers connect to two WLAN interfaces...
> E.g. the default-route, announced by the WRAP board, is 
> flapping between the two interfaces. This behaviour is an 
> effect of the Link Quality Extension - if it is turned off on 
> every router, the routing is based on hop counts and behaves ok.
> 
> My question is, whether somebody on this list has discovered 
> the same problems and if, what the solution was (if there's any!)
> 
> Thanks a lot.
> Take care,
> Rolf


I have a similar situation, but my links are not identical.  They both contain the same routes, but I prefer one of them over the other.  I broke out the two interfaces into their own section of the conf file so I could make the HnaInterval longer on the interface I'd rather not use.  This has the effect of a "preference", if you will, and keeps routes bound to one link unless it's outright down.

Maybe the same would work for you?


> 
> More Infos:
> ===========
> We're running the following olsr version:
> 
>   *** olsr.org - 0.4.10 ***
>   Build date: Jan 18 2006
>   http://www.olsr.org
> 
> And the configuration file:
> DebugLevel              0
> IpVersion               4
> AllowNoInt              yes
> Pollrate                0.1
> TcRedundancy            2
> MprCoverage             7
> LinkQualityFishEye      1
> LinkQualityWinSize      100
> LinkQualityDijkstraLimit 0 5.0
> Hna4
> {
>          10.248.251.64 255.255.255.224
>          10.248.251.96 255.255.255.224
> }
> LoadPlugin "olsrd_nameservice.so.0.2"
> {
>          PlParam "name"          "KSSG2"
>          PlParam "hosts-file"    "/rw/var/hosts"
>          PlParam "suffix"        ".olsr"
> }
> LoadPlugin "olsrd_txtinfo.so.0.1"
> {
>          PlParam "Accept" "127.0.0.1"
> }
> LoadPlugin "olsrd_httpinfo.so.0.1"
> {
>          PlParam "Port" "81"
>          PlParam "Host" "127.0.0.1"
>          PlParam "Net" "0.0.0.0 0.0.0.0"
> }
> IpcConnect
> {
>          MaxConnections  1
>          Host            127.0.0.1
>          Net 172.16.0.0 255.255.255.0
> }
> LinkQualityLevel 2
> UseHysteresis no
> Interface "eth0" "ath0" "ath1"
> {
>          HelloInterval           6.0
>          HelloValidityTime       108.0
>          TcInterval              4.0
>          TcValidityTime          324.0
>          MidInterval             18.0
>          MidValidityTime         324.0
>          HnaInterval             18.0
>          HnaValidityTime         108.0
> }
>