daemon-path.md

The Path of the Daemonist

1. The Neophyte (The Watcher at the Console)

Focus: Learning to observe, not yet to summon.

• Teachings:

  • Understand what a daemon is: background processes, terminal detachment, PID files.
  • Learn to identify running daemons (ps, top, htop) and read logs (journalctl, /var/log/).
  • Perform safe restarts with systemctl or init scripts — observe cause/effect.
  • Begin learning signals (kill -HUP, kill -TERM) and their meanings.

• Trial: Identify three rogue processes and correctly stop them without rebooting the host.

• Symbolic Rite: Granted the Watcher’s Key: permission to read logs and monitor process tables.

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2. The Initiate (The Binder of Ports)

Focus: Basic conjuration and safe containment.

• Teachings:

  • Manually daemonise a simple script (double fork, redirect I/O).
  • Create and manage PID files properly.
  • Configure basic logging (syslog vs. direct file).
  • Understand privileges: setuid, chroot, umask.

• Trial: Bind a trivial daemon (e.g., “heartbeat logger”) to a port and prove it survives logout.

• Symbolic Rite: Receives Vestments of Non‑Root — no longer trusted with root always, must learn humility.

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3. The Adept (Speaker of Signals)

Focus: Mastery of lifecycle and graceful service behaviour.

• Teachings:

  • Implement signal handlers (SIGHUP reload, SIGTERM shutdown).
  • Rotate logs gracefully without downtime.
  • Employ ulimit and resource constraints.
  • Integrate with systemd or supervisord as the modern invocation circles.

• Trial: Build a small daemon that handles reloads and exits cleanly under signal test.

• Symbolic Rite: Engraved with the Sigil of the PID — entrusted to write and lock PID files without summoning duplicate spirits.

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4. The Oathed Acolyte (Keeper of the Silent Process)

Focus: Discipline, service hardening, and secret knowledge.

• Teachings:

  • Employ cgroups, namespaces, or containers as binding circles.
  • Harden configuration (drop privileges, sandboxing).
  • Audit daemon behaviour with strace, lsof, and procfs.
  • Design failover rituals (watchdogs, health checks, auto‑resurrection).

• Trial: Survive the Chaos Monkey Night: daemon must restart automatically under simulated crashes, log flooding, and resource starvation.

• Symbolic Rite: Sworn on the Man Page Codex; granted the right to run kill -9 without seeking counsel.

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5. The Master Daemonist (Silent Architect)

(Optional final tier)

• Writes their own init systems or supervisord alternatives.
• Creates frameworks for others to daemonise services with ceremony and safety.
• Teaches new neophytes, continuing the lineage.

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Cultural Notes

• Oaths and Silence: Oath-taking is symbolic: “I shall serve unseen; I shall log all things, yet speak none.”

• Relics:

  • Watcher’s Key → access to /var/log/
  • Vestments of Non-Root → service account ownership
  • Sigil of the PID → right to /run

• Ritual Days:

  • Celebrate uptime anniversaries (e.g., 365d+ processes) with offerings of coffee and pizza.
  • Daemon’s Eve (traditionally a release night) is spent in vigil, watching logs in tail -f.