This script worked to reboot after a wedge. Assuming one has a
watchdog of course.
#!/bin/sh
if [ `id -u` != 0 ]; then
echo run as root
exit 1
fi
wdogctl -e -p 360 tco0
while true; do
echo -n "LOOP: "; date
date > /tank0/n0/do-wdog
sync
wdogctl -t
sleep 60
done