Release v3.1.0

Security

• mcctl-api IP allow list (#833): IP allow-list checks (including the default internal access mode) could be bypassed by a remote client. Update to 3.1.0. On an existing internal install, also bind mcctl-api to loopback (upgrade runbook 4-3). Until you update, block port 5001 from other hosts.

Upgrade

Run mcctl update (see the upgrade runbook).

• Existing internal installs: follow runbook 4-3 after updating.
• Game Mode: GAMEMODE in config.env never had an effect (the image reads MODE). Nothing is migrated automatically; saving Game Mode in the console moves it to MODE, so it first applies at the next start.
• mcctl world delete <world> now asks first; without a terminal it needs --force or -y.
• Router image and .env variables are unchanged.

Added

• Console: optional Sudo Password field in the server delete dialog, so the API can remove the server's .local hostname on hosts without passwordless sudo (#761).

Fixed

• New servers get the Java image their VERSION needs; 1.20.5/1.20.6 use java21 (#826).
• Console Game Mode now takes effect (MODE), mcctl mod add handles Leaf/Folia/Pufferfish, schedules changed with the CLI apply within a minute, console world upload honors WORLD_UPLOAD_MAX_SIZE (#826).
• mcctl update keeps pinned image tags (#798) and runs the server image step on CLI-only hosts (#825).
• CLI argument parsing: audit, mod add, create --version, op --level, negative numbers and -- (#824, #728).
• Worlds with legacy names can be deleted (#728); mcctl world delete asks for confirmation (#823); minor CLI follow-ups (#828).

Docs

Web console screenshots recaptured for v3; README and docs checked against the code (#822).

Full details: CHANGELOG.md