m2dev-server/docs/debian-runtime.md

Debian Runtime

This document describes the current Debian runtime layout used for the production VPS.

Scope

There are two separate repositories in the deployment:

• m2dev-server-src: source code, build system, smoke/login test binary
• m2dev-server: runtime files, configs, quests, systemd deployment files

The server does not run directly from a git checkout. The live instance runs from a separate runtime directory.

Directory Layout

Current layout on the VPS:

/home/mt2.jakubkadlec.dev/metin/
  repos/
    m2dev-server-src/
    m2dev-server/
  build/
    server-src/
  runtime/
    server/

Meaning:

• repos/m2dev-server-src: code changes, git history, tests
• repos/m2dev-server: runtime template and deployment assets
• build/server-src: out-of-tree CMake build
• runtime/server: live runtime tree used by systemd

Runtime User

The runtime user is:

mt2.jakubkadlec.dev

The user owns the runtime tree and build artifacts. Operational wrappers that need direct database access or privileged installation steps are run as root.

Services

The Debian deployment uses direct systemd units instead of a custom bash/python supervisor.

Main orchestration unit:

• metin-server.service

Sub-units:

• metin-db.service
• metin-db-ready.service
• metin-auth.service
• metin-game@channel1_core1.service
• metin-game@channel1_core2.service
• metin-game@channel1_core3.service
• metin-game@channel99_core1.service

Important behavior:

• metin-db-ready.service waits until the DB socket is actually listening before auth and game start
• clean shutdown exits now return success instead of fake failure codes
• Linux runtime currently uses epoll for fdwatch and a watchdog-thread checkpoint backend

Ports

Current service ports:

• 9000: internal DB socket listener
• 11000: auth
• 11011: channel 1 core 1
• 11012: channel 1 core 2
• 11013: channel 1 core 3
• 11991: channel 99 core 1

Client-facing login flow currently uses:

• auth: 11000
• first public channel: 11011

Deployment Notes

Typical operational commands:

ssh mt2
systemctl status metin-server
systemctl restart metin-server
journalctl -u metin-auth.service -n 100 --no-pager

Rebuild the login smoke utility:

sudo -iu mt2.jakubkadlec.dev \
  cmake --build /home/mt2.jakubkadlec.dev/metin/build/server-src \
  --target metin_login_smoke

Security Notes

Current operational stance:

• password SSH login is disabled
• root login is allowed only by SSH key
• production helper scripts that touch the DB directly are root-only
• runtime repo and source repo do not store secrets

Do not store production secrets in markdown, systemd templates, or git-tracked shell scripts.