BTW: it's this line (at the end of /usr/sbin/wondershaper) that's causing the trouble:
tc filter add dev $DEV parent ffff: protocol ip prio 50 u32 match ip src \
0.0.0.0/0 police rate ${DOWNLINK}kbit burst 10k drop flowid :1
And, indeed, removing "flowid :1" from that line causes wondershaper to complete successfully. I haven't been able to test whether it still limits bandwidth properly and maintains low latency under high transfer rates.
BTW: it's this line (at the end of /usr/sbin/ wondershaper) that's causing the trouble:
tc filter add dev $DEV parent ffff: protocol ip prio 50 u32 match ip src \
0.0.0.0/0 police rate ${DOWNLINK}kbit burst 10k drop flowid :1
And, indeed, removing "flowid :1" from that line causes wondershaper to complete successfully. I haven't been able to test whether it still limits bandwidth properly and maintains low latency under high transfer rates.