m2dev-server/docs/rollback.md

Rollback

This document describes the practical rollback workflow for the current Debian VPS.

Important Principle

There are two rollback surfaces:

• source rollback (m2dev-server-src)
• runtime-file rollback (m2dev-server)

They are related, but they are not the same repository and do not always need to move together.

Fast Safety Rule

Before a risky deploy, record both current commits:

ssh mt2
sudo -iu mt2.jakubkadlec.dev git -C ~/metin/repos/m2dev-server-src rev-parse --short HEAD
sudo -iu mt2.jakubkadlec.dev git -C ~/metin/repos/m2dev-server rev-parse --short HEAD

If the deploy fails, rollback to those exact commits.

Source Rollback

Use this when the regression is in:

• server binaries
• network code
• DB logic
• C++ runtime behavior

Example:

ssh mt2
sudo -iu mt2.jakubkadlec.dev git -C ~/metin/repos/m2dev-server-src checkout <good_commit>
sudo -iu mt2.jakubkadlec.dev cmake --build ~/metin/build/server-src --parallel "$(nproc)"
sudo -iu mt2.jakubkadlec.dev ~/metin/deploy/sync-runtime.sh
systemctl restart metin-server.service
/usr/local/sbin/metin-login-healthcheck

Runtime Rollback

Use this when the regression is in:

• configs
• quests
• locale files
• runtime-only scripts

Example:

ssh mt2
sudo -iu mt2.jakubkadlec.dev git -C ~/metin/repos/m2dev-server checkout <good_commit>
sudo -iu mt2.jakubkadlec.dev ~/metin/deploy/sync-runtime.sh
sudo -iu mt2.jakubkadlec.dev ~/metin/deploy/compile-quests.sh
systemctl restart metin-server.service
/usr/local/sbin/metin-login-healthcheck

Combined Rollback

Use this when the regression could be caused by an interaction between:

• new binaries
• new runtime files

Rollback both repositories together and rebuild/redeploy.

systemd Rollback

If the regression is in deploy/systemd/, rollback the runtime repository to a known good commit and re-run:

python3 deploy/systemd/install_systemd.py ... --restart

Verification After Rollback

Minimum verification:

systemctl status metin-server.service --no-pager
ss -ltnp | rg ':(9000|11000|11011|11012|11013|11991) '
/usr/local/sbin/metin-login-healthcheck

What Not To Do

• do not use git reset --hard blindly on a dirty VPS checkout
• do not rollback only one repository if the deploy changed both and the fault domain is unclear
• do not close the current SSH session before the healthcheck passes