sorcerykid wrote:<!-- snip -->
Came here to say this.
Festus1965 wrote:sorted (gold-)chest, even sort is OFF
wrong, as I meant they are touching my locked gold-chests, which I never sort, as I sort my way, but when they had access (a window or on a public place) they have been sorted from them
Players shouldn't be able to access locked chests, regardless of what client they're using. If players are able to do this, it's more likely that there's a bug/vulnerability in a mod that you are using (as sorcerykid suggested). In that case any player could potentially exploit it, not just those using unofficial clients.
Festus1965 wrote:can fast, fly - maybe noclip
wrong, we should analyze what a flying or noclip mean in the game.
fly mean be longer time a view nodes over an node that is not passable, mean to stand on - and it is not a falling, flying is an constant longer sequeny of not follow the gravity and change directions that NOT fix to falling or jumping actions
noclip is also indication, as surrounded of solid nodes over some time, sure I can dig in someone, but then he cant move, but theese guys just have seen on SONOS last week are long time IN several different positions without any air or air-like node
fast is more difficult, but as most used in combination ... sure can detect it for 80%
Network latency cannot allow "fast", "fly", and "noclip" for real but it can create effects that look the same. For example, if a player jumps and then lags at the top of the jump, it may look like they are hovering in the air for a few seconds. If they walk along while jumping, particularly over obstacles, it can look like they are flying. Similarly, if a player walks from point A to point B but lags while walking, to other players it will look like they were standing at point A for some time and then ran (fast) or even teleported to point B. Not completely sure about noclip but I think lag can sometimes cause players to end up inside blocks.
Festus1965 wrote:can store 65535 same items in his inventory, not only 99
oh thanks, then I think there is no any save server here, as I use only mods out of minetest.mods, don't change them and other things, as I am not able to do this - but your answer indicates that I could do it also as server is miss configured or mods. But to do this, a client need to use this failure/bug, and I have seen it !
If this is a bug in a mod, it can be exploited by all players not just those using unofficial clients.
Festus1965 wrote:just with login they have diamond armor (that is cheat ! my server))
thanks, that goes again to all this most used mods here ... nice to know, but I had them, just ready check IP and see them running from spawn in diamond armor, but sure 1st login.
Not sure what IP addresses have to do with this. You should be tracking the player's username, not their IP address. Players can connect from different IP addresses so you could have an existing (older) player connecting from a new IP address. If you track the IP address it will look like its the first time they've connected but if you track the username you'll see that their account is older. Not sure what user tracking/management mod you're using but it should be able to tell you the first login time or login count for a particular username rather than the IP address. IP addresses only become important if you've got a player creating multiple accounts to get around a ban.
In general, it appears that you may have some vulnerable mods on your server. Make sure that you are using up-to-date versions of all of the mods. Be especially careful if you have mods such as worldedit, or mods offering similar "edit anything" abilities to server admins, hackers can cause considerable damage if these mods are configured incorrectly or contain a vulnerability themselves (I believe worldedit had such a vulnerability a few years ago).
It would also be helpful to try to better understand concepts such as network latency/lag and what effects it has on the game, or what can happen if a player's client crashes or their connection drops for some reason. Many of the issues that you have described can be caused by this and aren't indicative of players using unofficial clients (or trying to cheat in any way).