Bukkit

@matagin

Best practices is to first find out which checks are too sensitive for your taste, then configure accordingly if possible.

Typically one would need to somehow isolate a situation.

If you have dedicated testers and a test server or a low player-count phase (really low) then you could go for in-depth logs and such, but i assume you will want to go for an online production server strategy, because installing extra plugins this is more like what an official "NCP-tester" would do, e.g. install TestNCP and create debug outputs etc.

So the best practices is about isolating the issue "as good as possible" - you have players that claim it does not work, the following steps:

• Call them in to reproduce the issue, or be there when they do something supposedly similar. If possible rely on players that are rock solid non-cheaters, to not have them use a hacked client, but random players might do too.
• Use the "ncp remove (player)" command to ensure no past-violations are recorded in the history, for the lazy "ncp remove *" does it neatly.
• Let the players fight/reproduce.
• Use "ncp info (playername)" to see what checks alerted. This will not be interpretable at a glance (warning!), because some checks generate high violation levels some don't, but the violation count 'n' can give an idea of what checks.

(Optional for the not-lazy: configure NCP to output more or any-at-all violation logs and do another iteration of the above).

Rather test a couple of times, e.g. during a tournament do "ncp remove (...)" and "ncp info (...)" and just dump the output to a file or copy from log/client-log later. Also include the nocheatplus.log entries for the time of testing and maybe the server.log, depending on what is turned on. Do remove/change ips and player names if you want so.

Just pm or "present" us the logs for a quick look.

One thing you can directly: set checks.fight.direction.strict to false (it seems too strict).
We are having fight checks in focus right now, so some default config and even implementation might change soon.

@arnofrutos

The pvp hacks do "work" and gain some advantage, but they should be limited by a lot, so at least a skilled fighter stands some chance to win.

So the interesting thing is how much they can do. We will try to reduce false positives for fight checks first, then we will advance towards making them more effective.

@GodsDead

Please elaborate on the terms "absolute" and spam-fest. What are your expectations? What is the matter (players spam, alert messages)? What plugins that might conflict do you have installed, like mcMMO , other skills/weapons/moving-features?

You can turn off notifications ingame with "ncp notify off" or by permission (see permissions page, nocheatplus.notify, nocheatplus.command.notify) or in the configuration. If you have a high player count, you might want to alter the configuration to notify less (configuration page), or turn it off - at least reduce file logging by focusing on either console or file or none of both.

@Shevchikden

Not that it need to be related, but your version of NCP is clearly outdated, i suggest to switch to the current development branch, like "mostly stable" build 655.

Concerning the issue, i doubt that CoordMap.put can hang your server, more likely seems to be a deadlock caused by ... other plugins + Spigot.

(Technically it seems that the SimplePluginManager from Bukkit is waiting on a monitor during some event is about to get fired, while NCP is processing an event in the main thread (unless some nasty plugin fires a projectile-launch-event asynchronously, which would then be the culprit) - so probably the WorldSaveEvent is fired asynchronously with Spigot, which then could lead to trouble, in case plugins and/or PluginManager are not prepared for it.)

We will keep an eye on such of course, but currently i can't see a cause on side of NCP.

@theIgloo

Ok, i see. Creative mode + tnt - It mainly launches the player upwards?

@szebi1999

Thanks. Why do you think it lags your server?

@MyPictures

@Welite

I wouldn't reference "NoPwnage" too much, in fact. We do implement the checks for the message itself and more, but we don't implement the proxy-lookup, which is what NoPwnage was centered around, unless i am mistaken. The chat checks should not cost you much extra.

@Stevensaurus

That's interesting - i think there is a ticket for that already: Can you add a comment on 684? I am interested in the output of the "ncp version" command, what kind of slabs, i.e. occupying the upper or lower part of a block, and if it can be reproduced without the ctrl-sprint feature.

@Shevchikden

Does your server crash more often? Does this very log repeat?

@theIgloo

Can you be more specific? Are players in urvival mode or creative mode? You are using pistons? Any other special blocks involved ?

If you are using pistons, Ticket 364 should be related. Problem with pistons is that it needs monitoring pistons "a lot", i.e. all, and keep it in memory in order to allow for latency (...) - then again it might need adaptions for all the flexibility then with the on-ground checking. Not impossible but certainly not simple to implement and not likely to come very soon.