Back up before updating

1. Stop the Minecraft server normally.
2. Copy the plugin's entire folder from plugins/ to your private backup location.
3. Keep a copy of the working plugin jar.
4. Start the server again.

For example, back up both plugins/GsSpawners/ and plugins/GsSpawners.jar.

The folder includes settings, databases and activation files. Do not publish it or send the whole folder in a public support channel.

Restore a backup

Stop the server, restore the matching folder and jar, then start it. Test restores on a separate copy before relying on them.

Advanced: live backups

Use SQLite's backup API for an online database backup. Copying only a .db file while the server is writing can miss data in its WAL file. Stopping the server first is the easiest option.