How do I figure out who was playing my Minecraft realm at a specific time?

Question

I have a Minecraft Realm for my kids and recently opened it up to allow their friends to join the realm. There have been a few incidents since then where something was lost, destroyed, stolen, etc. I know I can look at backups to figure out when something changed and sometimes I can look at last login time to figure out who was playing, but is there any way to look at who was playing in backups that pre-date the last login?

I found an older question about using NBTExplorer, but that doesn't seem to work with MCPE v1.12 and I am hoping that there is an alternative?

Kids are playing on iPads and Nintendo Switches - I use an iPad. Also, I don't have access to a Windows computer, only a Mac.

Answer 1

How

Assuming you're okay with using command blocks you can kinda set up a trap like this:
Type this in the chat while in-game on any opped account:

/give @s repeating_command_block

Now type this:

/gamerule commandblockoutput false

You must be in creative mode.
Then you can put a bait chest down, maybe put diamond or something in it.
Place the command block a few blocks below the chest and put this command into the input field:

tag @a[r=20] add sus

Then on the left there will be a select bar that says "Needs Redstone". Click on it and select "Always Active".

Now you can always type this in the chat window:

/testfor @a[tag=sus]

Now anyone who entered the area who is online will appear in chat. This will be permanently attached to them unless you were to manually remove it.

Notes

• Of course not everyone who enters the area is nefarious, so make sure to put it somewhere it is obvious you are not allowed to go
• Everyone will appear, so your kids and you included. Obviously you can ignore yourself.
• Only people online will appear, however once they rejoin the game will still remember, so it will be permanently attached to them.
• Don't fret! Other players will not be able to pull up the GUI you used to make this system, and they cannot break the block either.

Cons/Solutions

• Only people online will appear, you can use Universal Minecraft Editor if you send a world to the Mac, but I will not go over how to do that as that is rather complicated and I am not sure how to look through someone's tags.

Answer 2

According to any info about Realms I can find, it doesn't keep any sort of logs that can be accessed by the owner; therefore there is no way to check who was on it when beyond the last login.

Features such as a proper record of login times, chat logs, etc. are only part of a "real" server, whether hosted through a hosting company or run on a computer of your own. Unfortunately Realms' ease of use also limits its features.

Answer 3

This solution isn't perfect for finding out who was online at a Specific time but will work to know who was last online.

You'll need to set up two command blocks, on a loaded timer in a loaded chunk.

(you make the timer using 2 hoppers and some pistons with a redstone block underneath, see hopper timers

command block one you make a regular command block, with the redstone from the hopper timer leading in. you type '/give @a Allow' (this will give everyone online a block called 'Allow' unobtainable in creative or survival.

command block two you make a conditional chain command block leading out (see the arrows on the command blocks) of the previous one. In this command block you'll type '/clear @a Allow' (this will take said block away from any online players)

And voila! You just check the second command block's previous output (make sure they're set to display previous output) to see who was last online! You'll have to this as soon as you log in, or it will clear the last check and will display your name. I'm currently working on a way of logging this into a book or something but for now this is the best solution I could find.