Changing the npcConfig.xml's FleetClasses will cause the server to go into a bad state after about 15-20 minutes.
When in this state you'll see the following:
* All current players will lag out
* Any new connection attempt will time out, though it will 'connect' then timeout. This is visible in the server logs
* Not even the StarNet.jar tool can talk to the server, does not give an error, just returns no output
* Restarting the server will just put it back into the same state
* Server does not seem to log any errors that indicate something bad is happening.
* Server will refuse to exit when sending a SIGTERM, you need to send it a kill -9 in order to stop it.
* Only fix seems to be to blow away the server database and start anew(and or corse change the FleetClasses back to what it use to be).
setting I tried for FleetClasses:
<FleetClasses>
<FleetClass>
<!--Blueprint classes going to be added to a fleet of this class in looping order-->
<Type>ATTACKING</Type>
<Classes>ATTACK</Classes>
</FleetClass>
<FleetClass>
<!--Blueprint classes going to be added to a fleet of this class in looping order-->
<Type>DEFENDING</Type>
<Classes>ATTACK</Classes>
</FleetClass>
<FleetClass>
<!--Blueprint classes going to be added to a fleet of this class in looping order-->
<Type>SCAVENGE</Type>
<Classes>SCAVENGER, MINING</Classes>
</FleetClass>
<FleetClass>
<!--Blueprint classes going to be added to a fleet of this class in looping order-->
<Type>MINING</Type>
<Classes>MINING, ATTACK</Classes>
</FleetClass>
<FleetClass>
<!--Blueprint classes going to be added to a fleet of this class in looping order-->
<Type>TRADING</Type>
<Classes>CARGO, ATTACK</Classes>
</FleetClass>
</FleetClasses>
Server log attached: {F11406}