On Thursday, April 8, 2021 7:56:29 AM CEST joe@careyhome.org wrote:
> Hi Everybody,
> 
> I'm running BATMAN v 2019.2 with ath10k on OpenWRT.  The particular router
> I'm using has two interfaces, 2.4 GHz and 5GHz.  With each router using
> single interface (e.g. 2.4 GHz), it works fine.  When I add a second
> interface (e.g. 5GHz), it sometimes hangs.
> 
> I know that BATMAN is expected to alternate between the two interfaces, but
> that doesn't seem to be working.  As you probably know, using two
> interfaces should dramatically improve throughput if you need to make a hop
> through another mesh node.
> 
> To verify this is the problem, I did a test where I ran three routers,  2.4G
> <> Dual (2.4G & 5G) <> 5G.  I would try to ping between the two routers
> that were using just a single interface.  Obviously, that must hop through
> the dual radio router.  The dual radio router has both interfaces on the
> bat0 master, and batctl reports they're both active.
> 
> The system would sometimes lose link, although batctl would report getting
> neighbor messages.  Even using the batctl ping function doesn't get
> through.  I can see traffic flowing on both the 2.4 GHz and 5GHz
> interfaces.
> 
> I'm happy to provide lots of configuration detail, but I thought I'd start
> with a high level description in case this is a known problem.
> 
> Any assistance is appreciated.  Thank you,
> 
> --Joe

Hi Joe,

I'd expect your setup to work. Could you try to run "batctl ping" between the 
nodes, maybe also on the intermediate links? If you see that it's failing too, 
could you set up some IPv4 addresses (or use IPv6 link local addresses) on 
your ad-hoc/mesh interfaces, and try to ping to the next hop? I suspect that 
something is off with the wifi driver, i.e. broadcasts are still working but 
unicast pings are dropped. 

Cheers,
        Simon