2015-05-21 17:11:22

by Jason Scatena

[permalink] [raw]
Subject: Issues with mesh networking path detection

Hello all,

I am attempting to set up a mesh network between 4 computers with
Atheros 9271 based usb wifi dongles using the ath9k driver.

I followed the guide at: https://github.com/o11s/open80211s/wiki/HOWTO

to set up the network.

When I get all of the computers up and configured they all see each other.
The command "iw dev mesh station dump" shows all the nodes in the
area. However the path selection doesn't seem to work at all. For
instance the command "iw dev mesh mpath dump" returns nothing. However
if I manually add arp entries using the arp command they show up in
the mpath dump.

I am willing to do whatever to troubleshoot however there is very
little documentation that I have been able to find on trouble shooting
these issues. I would also be able to provide a pcap file of the nodes
coming online.

I'm new to the wireless world but have C coding experience and would
be willing to put in the time to learn.

Best,
Jason Scatena


2015-05-21 17:25:11

by Oleksij Rempel

[permalink] [raw]
Subject: Re: Issues with mesh networking path detection

Am 21.05.2015 um 19:11 schrieb Jason Scatena:
> Hello all,
>
> I am attempting to set up a mesh network between 4 computers with
> Atheros 9271 based usb wifi dongles using the ath9k driver.
>
> I followed the guide at: https://github.com/o11s/open80211s/wiki/HOWTO
>
> to set up the network.
>
> When I get all of the computers up and configured they all see each other.
> The command "iw dev mesh station dump" shows all the nodes in the
> area. However the path selection doesn't seem to work at all. For
> instance the command "iw dev mesh mpath dump" returns nothing. However
> if I manually add arp entries using the arp command they show up in
> the mpath dump.
>
> I am willing to do whatever to troubleshoot however there is very
> little documentation that I have been able to find on trouble shooting
> these issues. I would also be able to provide a pcap file of the nodes
> coming online.
>
> I'm new to the wireless world but have C coding experience and would
> be willing to put in the time to learn.


Hi,

i don't think there are people who will know the answer without research
and reading the code.

Since you are willing to learn any way, fallow the codepath and find out
what is happening. We would be happy to have more wifi experts :)

Find out what executed in kernel if you start this command: "iw dev mesh
mpath dump". I assume it is starting somewhere in linux/net/wireless/mesh.c

Use printk() placed in code or use gdb+openocd+jtag if you use some arm
or mips system.


> Best,
> Jason Scatena
> --
> To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>


--
Regards,
Oleksij


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2015-05-21 17:32:50

by Alexis Green

[permalink] [raw]
Subject: Re: Issues with mesh networking path detection

Keep in mind that mpath table is going to empty unless you try to
reach another node. Assuming your routing is correct, pinging from one
node to another should initiate ARP request, which will cause path
requests to go out and, ultimately, add entries to mpath table. I
didn't see any mention of attempting to send data packets across the
mesh, so that might be the only problem.

On Thu, May 21, 2015 at 10:24 AM, Oleksij Rempel <[email protected]> wrote:
> Am 21.05.2015 um 19:11 schrieb Jason Scatena:
>> Hello all,
>>
>> I am attempting to set up a mesh network between 4 computers with
>> Atheros 9271 based usb wifi dongles using the ath9k driver.
>>
>> I followed the guide at: https://github.com/o11s/open80211s/wiki/HOWTO
>>
>> to set up the network.
>>
>> When I get all of the computers up and configured they all see each other.
>> The command "iw dev mesh station dump" shows all the nodes in the
>> area. However the path selection doesn't seem to work at all. For
>> instance the command "iw dev mesh mpath dump" returns nothing. However
>> if I manually add arp entries using the arp command they show up in
>> the mpath dump.
>>
>> I am willing to do whatever to troubleshoot however there is very
>> little documentation that I have been able to find on trouble shooting
>> these issues. I would also be able to provide a pcap file of the nodes
>> coming online.
>>
>> I'm new to the wireless world but have C coding experience and would
>> be willing to put in the time to learn.
>
>
> Hi,
>
> i don't think there are people who will know the answer without research
> and reading the code.
>
> Since you are willing to learn any way, fallow the codepath and find out
> what is happening. We would be happy to have more wifi experts :)
>
> Find out what executed in kernel if you start this command: "iw dev mesh
> mpath dump". I assume it is starting somewhere in linux/net/wireless/mesh.c
>
> Use printk() placed in code or use gdb+openocd+jtag if you use some arm
> or mips system.
>
>
>> Best,
>> Jason Scatena
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
>> the body of a message to [email protected]
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>
>
>
> --
> Regards,
> Oleksij
>