[Olsr-users] Curious about OLSR on AirOS, compared to OSPF, Quagga

[Ben West]

Hi Michel,

My investigation into AirOS has been motivated by experience running OpenWRT
v8.09-derived ROBIN mesh firmware on Bullet2HPs specifically, exposing a
couple problems with madwifi on this type of device:

1. Minstrel rate algorithm ignoring feedback and sticking at particular rate
https://dev.openwrt.org/ticket/8683 (received wontfix from the developer)
http://sourceforge.net/mailarchive/message.php?msg_id=25803543 (same bug
reported on madwifi r4133)
http://dev.open-mesh.com/wiki/ng-changelog?version=10 (a possible fix in
OpenWRT ng, r274)

2. "wifi0: transmit timed out," where the ap simply drops connectivity for a
few seconds
http://www.assembla.com/spaces/RobinMesh/tickets/13-netdev-watchdog--wifi0--transmit-timed-out-on-bullet2hp
The response from a moderator on the Ubnt forum to a similar query about
this problem is, "Your device is operating in busy environment and radio
isn't able to transmit any packets to the air. I do recommend to change
channel, channel width and try channel shifting. Also to hear less AP
around, you can decrease TX power as well."
On the ROBIN firmware stack, this happens consistently on Ubiquiti 2.4GHz HP
devices like Bullet2HP and Pico2HP. However, the ROBIN devs make this
problem go away with madwifi by simply compiling their firmware against
OpenWRT v8.09.2 instead of v8.09.1.  So, it appears no elegant solution
exists.

I understand that AirOS kernel version is presently too old (or Ubiquiti's
willingness to respond to feature requests too small) to support dynamic
routing schemes.

Certainly, if OpenWRT + ath5k/ath9k is known to not suffer these problems on
Bullet2HP and M-class devices, I'm interested in looking into it.

On Wed, Feb 23, 2011 at 8:27 PM, Michel Blais <(spam-protected)>wrote:

> Here, we are using openwrt with olsr on rspro for routing and airos in
> bridge mode for wireless link. Anyway, airos don't give enough option to
> make good router, you will end up requesting new feature like everybody else
> on the forum when ubnt focuses on bridge mode with basic router options.
>
> Mike
>
> 2011/2/23 Ben West <(spam-protected)>
>
>> Hi All,
>>
>> My apologies upfront if some of these are rank newbie questions.
>>
>> I also realize this message harkens back to a long thread last month about
>> patching Ubiquiti AirOS with OLSRd (before I subscribed), but I'm curious if
>> anyone may have experience to share on current state of OLSR under AirOS vs.
>> other dynamic routing schemes such as OSPF/Quagga.
>>
>> I've described my experience testing the Funk Feuer-patched AirOS 5.2
>> images on 5GHz devices to this thread on the Ubiquiti forum.  I posted there
>> since I was curious about creating a hidden node situation with the testing.
>> http://www.ubnt.com/forum/showpost.php?p=155993&postcount=55
>>
>> Plus, I see that ninux.org have recently (this month) released their own
>> patched version of AirOS, based on that from Funk Feuer.
>> http://wiki.ninux.org/NanostationM5AirOSModOLSR
>>
>> By manually specifying default routes b/w nodes (described in the
>> ubnt.com thread above), I can indeed effect multi-hop paths, but I
>> believe this effectively overrides the OLSR service.  Is this presently the
>> only option for multi-hop routing on AirOS?
>>
>> I see there are already AirOS images patched with Quagga/OSPF, which I'm
>> considering deploying in the mean time, as my intended mesh topology is
>> quite simple.
>> http://dren.dk/ubi.html
>> http://dren.dk/airos-plus.html
>> http://www.ubnt.com/forum/showthread.php?t=23209&highlight=quagga
>>
>> http://wiki.inveneo.org/index.php/InveneoUbntFirmware#Firmware_for_Ubiquiti_Devices
>>
>> Is my understanding correct that, from a high level, one key feature which
>> OSPF does not provide w.r.t to OLSR is multi-hop routing?
>>
>> (P.S. My motivation to try out AirOS comes from difficulties running
>> OpenWRT/madwifi firmware like Open-Mesh on Ubiquiti 2.4GHz devices.  Madwifi
>> operation seemed to be particularly spotty on devices like the Bullet2HP,
>> suggesting Ubiquiti had incorporated driver/kernel tweaks into their SDK for
>> speed and stability.)
>>
>> --
>> Ben West
>> (spam-protected)
>>
>> --
>> Olsr-users mailing list
>> (spam-protected)
>> http://lists.olsr.org/mailman/listinfo/olsr-users
>>
>
>


-- 
Ben West
(spam-protected)
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