[Olsr-dev] OLSR1: sendto IPv4 Resource temporarily unavailable / affects other neighbours

[Henning Rogge]

On Sat, Sep 27, 2014 at 10:50 AM, Bastian Bittorf
<(spam-protected)> wrote:
> * Henning Rogge <(spam-protected)> [26.09.2014 15:35]:
>> Can you access some timing data if the link medium was considered
>> "free" or "busy" during the blocking time?
>>
>> Should be available with the iw tool.
>
> how exactly? iw event?

I think its "iw ... survey dump" or "iw ... passive scan" (or
something like this).

> also: i tried to reproduce the problem with:
>
> iptables -D OUTPUT -p udp --dport 698 -o $WIFIDEV -j DROP
>
> but this only affects the wifi-link, not the wired ones...
> (syslog message is: OLSR: sendto IPv4 Operation not permitted)

When OLSRd (1) was written nobody thought about the case that a write
to a socket would block. I think most sockets just give you the error
message you saw above, but this still means the local OLSRd cannot
send any kind of packet, which degrades all links.

As long as the error messages come, OLSRd is still working... its just
that some interfaces don't work anymore.

Henning