Re: Inquiry about Communication Issue between Nodes in "ONLY two nodes mesh network" with batman-adv

Re: Inquiry about Communication Issue between Nodes in "ONLY two nodes mesh network" with batman-adv

[Simon Wunderlich]

On Monday, October 16, 2023 4:12:41 PM CEST XU Yang wrote:
> Dear maintainer,
> 
> I am a developer currently using the batman-adv library in research and have
> encountered some issues that I hope you might be able to assist with.
 
> In setting up a mesh network using batman-adv, I've noticed that when only
> two nodes are present in the network, they are unable to communicate with
> each other. However, once a third node is introduced, all nodes can
> communicate normally. Further testing has revealed that even with two
> nodes, despite good ad-hoc wifi connection quality, the nodes remain
> invisible to each other.
 
> Here are the system and configuration details:
> 
> Hardware: Jetson Orin NX with rtl8822ce
> Operating System: L4T r35.3.1 Ubuntu20.04
> batman-adv version: 2023.2-9-g5fecd4a3
> 
> The configuration code we use is in the attachment.
> 
> 
> I appreciate your time in reading this email and look forward to your
> response. I hope you might be able to help me understand the cause of this
> issue and suggest possible methods to resolve it.

Hi Young Xu,

this sounds like a underlying Wi-Fi driver issue. You may want to set up IP 
addresses on the base Wi-Fi interfaces (e.g. wlan0) and try to ping between 
the nodes directly, without batman-adv. You may also check further with "iw 
wlan0 station dump" (or similar) who receives packets by whom, or check with 
tcpdump if you see the OGM broadcasts.

I haven't seen many Realtek Wi-Fi devices to use batman-adv, and at least in 
the past my experience with those devices not very positive, so also for that 
reason I'd look into driver related issues first.

Cheers,
       Simon