Connectivity
Modby someaddon
Fix Login timeouts, Packet sizes errors, Payloads errors, ghostblocks and more.
Type
Mod
CurseForge Downloads
136,189,274
CurseForge ID
470193
Last Updated
Apr 13, 2026
Description
Lightweight mod which solves several connection problems like Login-Timeouts, DecoderException, Packet size limits, Ghostblock issues, Payload too large and more. It also offers commands to analyze network traffic and a bunch of debugging utilities, advanced error logging, packet logging etc.
Requires Cupboard dependency to be installed in newer versions
- Login timeout
- Play timeout
- Detailed Network statistics
- Fix packet size exceptions during login/play
- Log data of too large packet to show sources
- Log warnings about too large data beeing sent
- Malformed/Malicious traffic protection
The mod is not required on both sides, but offers useful functionality for both sides.
Randompatches (in)compatibility:
Set this in the randompatches.toml config file so random patches does not crash when started alongside connectivity:
mixin_blacklist = ["ServerPlayNetHandlerKeepAlive"]
Connectivity has some overlap with randompatches and happens to apply first, which makes random patches crash.
Timeoutout/XL packets mod is incompatible/not needed alongside this

If you enjoy this mod consider supporting the development, any support is greatly appreciated.
The development is an unpaid free-time activity, so any support helps being able to spend more time on it.
You can support me on Patreon or just spreading the word around.
Network stats and Commands:
Commands for network stats show the traffic rate aswell as which packet is causing it. kb is short for kilobyte
Statistics are refreshed once per minute and save a history of up to 5 minutes. All commands have an optional minute count you can give it to display(1-5, 5 is default when no argument is given)
Normally most traffic is caused by chunk packets, modded packets should rarely exceed those.
Client side command to show outgoing traffic: /connectivity packetsClient
Server commands:
List traffic rate of all players: /connectivity packetsAllPlayers![]()
List packets by type send to a specific player(example is player Dev): /connectivity packetsPlayer Dev

List all packets sent out by the server by packet type. /connectivity packetsSummary

Print the largest packet of a type to the latest.log, e.g. the packet called MovePacket: /connectivity printpacket MovePacket
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