A friend of mine has been having intermittent problems connecting to the server, which we eventually tracked down to the cellphone network. Long story short, if too much data is sent via UDP in too short a time then the connection process somehow jams up and progress entirely fails. It affects multiple games -- really it's a problem with the internet connection, but I thought I'd report in case you feel like reading packet traces.
The problem disappears if you limit the bandwidth usage, either via the server config file (this is easy, but affects all clients), or via Linux traffic shaping. I've included "fix_neros_terrible_connection.sh" in the event someone else finds this thread via a google search; the script should be called as "./fix_connection.sh [IP address of problematic client]".
Code: Select all
#!/bin/sh
DEV=eth0
IP="$1"
sudo tc qdisc del dev $DEV root
sudo tc qdisc add dev $DEV root handle 1: cbq avpkt 1000 bandwidth 100mbit
sudo tc class add dev $DEV parent 1: classid 1:1 cbq rate 4mbit \
allot 1500 prio 5 bounded isolated
sudo tc filter add dev $DEV parent 1: protocol ip prio 16 u32 \
match ip dst "$IP" flowid 1:1
sudo tc qdisc add dev $DEV parent 1:1 sfq perturb 10
This will delete any other traffic classifier you've setup, but by default there are none. If you're the sort of person who's written one then I'm sure you'll be fine.
Anyhow, attached is tcpdump output from one attempt at connecting, without any such limiter in place.