Linux_post_install/DOC/howto/docker.md

How-To: pos docker

Manage self-hosted services, watch containers, and spin up disposable VMs. Tools: compose, ps, health, vbox.

Tool	What it does
pos docker compose	ScaleTail service manager (deploy/stop/logs/update)
pos docker ps	Enhanced container overview (health, IPs, ports, uptime)
pos docker health	One-glance health dashboard (exits 1 if unhealthy)
pos docker vbox	Disposable Docker containers as lightweight VMs

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pos docker compose — self-hosted services (ScaleTail)

Deploy 119+ self-hosted service templates (Jellyfin, Home Assistant, …) on Tailscale. Template set lives in /usr/local/share/linux_post_install/scale-tail/services/.

pos docker compose ls                      # list available templates
pos docker compose installed               # what's deployed locally
pos docker compose up jellyfin             # deploy or start
pos docker compose down actual-budget      # stop + remove
pos docker compose restart home-assistant
pos docker compose logs jellyfin -f        # follow logs
pos docker compose update                  # pull latest templates + refresh deployments
pos docker compose config                  # show global config
pos docker compose config set TS_AUTHKEY=tskey-auth-xxxxx
pos docker compose config set TZ=Asia/Tokyo
pos docker compose config set SERVICES_BASE=/data
pos docker compose config edit             # open global config in $EDITOR

Config strategy (three layers, each overrides the one above)

1. Template defaults — …/services/<name>/.env
2. Global config — ~/.config/linux_post_install/compose.env keys: TS_AUTHKEY | TZ | DNS_SERVER | SERVICES_BASE
3. Per-service config — /srv/<service>/.env (or $SERVICES_BASE/<service>/.env)

On first up, the per-service .env is generated from the template + your global config, and is never overwritten afterwards (not even by update).

Quick start

pos docker compose config set TS_AUTHKEY=tskey-auth-xxxxx   # required
pos docker compose up jellyfin
# open https://jellyfin.tail-xxxxx.ts.net

Recipes:

• Change timezone once, applies everywhere: pos docker compose config set TZ=Asia/Tokyo
• Store deployments on a bigger disk: pos docker compose config set SERVICES_BASE=/data
• Tweak one service's options after deploy: edit /srv/<service>/.env directly (never clobbered).

Troubleshooting:

• up fails with auth errors → TS_AUTHKEY missing/expired; re-set it.
• Service reachable only on the host → Tailscale up/tailscale up not running; check TS_AUTHKEY in the service .env.
• update doesn't change your customizations → expected; per-service .env is preserved by design.

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pos docker ps — better docker ps

pos docker ps

Enhanced overview: health status, uptime, IPs, port mappings.

Recipe: pair with the daily digest — the health report summarizes unhealthy/restarting containers; when it flags one, pos docker ps shows the details (IPs/ports/uptime) to investigate.

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pos docker health — is everything healthy?

pos docker health

Prints health + uptime per container; exits 1 if any container is unhealthy (useful for scripts/CI/monitoring).

Recipe: alert on failure in your own script:

pos docker health >/dev/null || notify_send "Docker unhealthy"

Troubleshooting: a container shows no health status if its image has no HEALTHCHECK — that's fine, it counts as "no healthcheck configured" (exit 0), not unhealthy.

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pos docker vbox — disposable VMs

Docker containers with a bind-mounted host dir so files persist even after the container is removed. Great for labs, downloads, kali, throwaway services.

pos docker vbox create lab1                        # default dir ~/lab1
pos docker vbox create lab1 --dir .                # files land in cwd
pos docker vbox create lab1 --dir /mnt/data/lab1
pos docker vbox create kali kalilinux/kali-rolling # custom image
pos docker vbox enter lab1
pos docker vbox stop lab1
pos docker vbox start lab1
pos docker vbox rm lab1
pos docker vbox ls

Recipe: a disposable browsing/download box:

pos docker vbox create dl --dir /mnt/data/dl
pos docker vbox enter dl       # work inside; files persist in /mnt/data/dl
pos docker vbox rm dl          # container gone, files kept

Troubleshooting:

• enter needs a shell/SSH-capable image; kalilinux/kali-rolling works.
• If files "disappear" after rm, check you used --dir on a real path — the container image changes are lost, only the mounted dir persists.

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Related

• Reference + compose config strategy: DOC/POS.md → docker
• Container health in the daily digest: system.md → health