Soekris Crash Duplicated in the Lab

Continuing the saga of the crashing Soekris Net5501 running OpenWRT… In the lab I now have a setup like the picture below. My laptop is connected to the OpenWRT router taken from the college on Skye, and on the far side of it is identical Soekris hardware running FreeBSD.

The two soekris routers are connected with three of their ports in parallel, i.e. eth0 connected to vr0, eth1 connected to vr1, eth2 connected to vr2 (FreeBSD names its interfaces according to the kind of driver/chip they use).

The laptop generates traffic travelling via the OpenWRT router to the FreeBSD router. It does this using the iperf tool run like so:

iperf -c 10.0.0.2 -u -b 20000000 -t 3600
iperf -c 10.0.1.2 -u -b 20000000 -t 3600
iperf -c 10.0.2.2 -u -b 20000000 -t 3600

this will fill up each of the three links between the routers with approximately 20Mbps worth of UDP traffic each (for an hour).

In fact with only two of these running the OpenWRT host will reliably crash in a matter of minutes. Nothing whatsoever on the console, no stack traces or memory dumps, nothing. With only one running the OpenWRT router seems stable enough, it didn’t crash after a day or so with far more traffic being pumped through it.

The same setup with both routers running FreeBSD seems to be solid, so far so good.