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

[Bastian Bittorf]

* Henning Rogge <(spam-protected)> [04.10.2014 18:27]:
> > 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.

i debugged more: when this happens there is a storm of OLSR-packets
on these nodes: 200 Kilobyte/s outgoing and 100 Kilobyte/s incoming
UDP-traffic on port 698 - this explains the situation 8-). With tcpdump
it looks like ...HNA-messages from a "weak" connected OLSR-cloud with
~150 nodes. i will debug further and keep the list informed...

bye, bastian