I guess it would be best to allow only the IP adresses of known server list sites to use UDP on the query port, so you'd be immune to DDoS, but...
Query isn't essential. At least my server worked fine with all inbound UDP traffic blocked. If query is needed, one could make a script which...
If you have dedicated box (and IP), you can firewall off all UDP traffic, because Minecraft server requires only TCP to work. That way you're...
PEX is one of the few that support MySQL. It is also much richer in features than other permission plugins. Unfortunately, this comes with the...
Use ramdisk for worlds, make MySQL innodb cache bigger. Java garbage collector settings help a lot too.
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