SafeSync

Player data sync between the servers of a network (Paper or Folia, behind Velocity or BungeeCord): inventory, ender chest, health and XP follow the player from one server to the next, never duplicated, never lost. MySQL or MariaDB only: no Redis, nothing on the proxy.

The proxy connects a player to the new server before it disconnects them from the old one, so the new server can read the data before the old one has written it. That is where items get duplicated or whole inventories disappear. Every such case has a defense in SafeSync and a bot test that fails when the defense is removed.

Free edition

The duplication and loss safety is the same as in the full edition.

• 2 servers synced together (one group), plus as many standalone servers as you want (lobby, creative).
• Inventory with armor and off-hand, ender chest (items byte for byte: components, plugin data, full shulker boxes), health, hunger, experience. Each data can be switched off.
• Conflicts kept for an admin (/safesync conflicts, view, apply, discard): nothing is overwritten without a copy.
• First install: the local data a player has on the other server is kept, never overwritten in silence.
• Paper and Folia. English and French, editable texts.

Never duplicated, never lost

Checkout in the database (the new server waits until the old one has written), save of the real state after a death (never a second death), every player saved before a stop, saves off the game thread, stale checkout taken back after a crash, a single owner when a player is on two servers at once, cursor and crafting grid given back before the save, everything cancelled while loading, local journal on disk when the database is down, late writes refused and kept as conflicts, newer-version data not loaded by older servers.

What a crash can cost: at worst the play since the last regular save (2 minutes by default, adjustable). Never an item in double, never the whole inventory. Tested by killing the server (kill -9) at each step of a player's departure.

Full edition (12.99 USD)

Unlimited servers and groups; potion effects, game mode, flight, statistics, advancements, location and plugin data (off by default); time-stamped history with preview and restore (chest menu on Java, form on Bedrock); import from HuskSync and MySQL Inventory Bridge; Floodgate account linking with a claim box; transfer log; PlaceholderAPI.

Requirements

• Paper or Folia 1.21.4 to 26.x, Java 21+ (tested on Paper 1.21.11, Paper 26.3 and Folia 26.3)
• MySQL or MariaDB, the same database for every server. Same group, a different server-name on each server.
• Not compatible with per-world inventory plugins (Multiverse-Inventories, PerWorldInventory). Money is not synced.

Commands

Links

• Documentation: https://github.com/TheMax98000/SafeSync
• Bug reports: https://github.com/TheMax98000/SafeSync/issues
• Full edition: https://payhip.com/b/EMXB7