What the installer changes

The installer writes only the paths it owns. Application containers and unrelated Docker resources are not adopted or reconfigured.

Paths

Path	What it contains
/etc/shipper/	Ownership marker, pinned image, Docker socket group, and the control-plane Compose file
/etc/shipper/instance.env	SHIPPER_IMAGE, SHIPPER_DOCKER_GID, and any instance environment you add
/var/lib/shipper/	SQLite database, encryption key, setup token, dashboard domain, update request and update status
/var/lib/shipper-installer/	Install log, host status, previous image record, and interrupted-update state
/etc/systemd/system/shipper.service	Starts the control plane after Docker and waits for health
/etc/systemd/system/shipper-host-status.timer	Records boot service, reboot, security update, clock sync, and update helper readiness
/etc/systemd/system/shipper-update.path and .timer	Watches for update requests and runs the host updater
/usr/local/bin/shipperctl	claim, rotate-claim, reset-password, reset-factor, status, and logs
/usr/local/libexec/shipper-update	Privileged update helper used by Settings → Updates
/usr/local/libexec/shipper-host-status	Host status collector used by the dashboard

When Docker must be installed, the installer also writes the signed Docker package repository configuration to /etc/apt/keyrings/shipper-docker.asc and /etc/apt/sources.list.d/shipper-docker.sources.

Control-plane container

The control-plane container:

• Runs as UID and GID 65532.
• Keeps a read-only root filesystem.
• Drops Linux capabilities.
• Mounts /var/lib/shipper at /data.
• Mounts the Docker socket read-only at /var/run/docker.sock.
• Publishes the control plane on port 8080.
• Uses unless-stopped restart policy and bounded JSON logs.

The Docker socket still grants host-level control. Treat the dashboard as a privileged operations surface.

Services

shipper.service is a systemd oneshot service that runs Docker Compose and waits for the control plane to become healthy. It depends on Docker and starts after the network is online.

The host status timer writes a small JSON file used by the dashboard. The update path unit watches /var/lib/shipper/update-request.json and starts the privileged update helper. The update service is separate from application workloads.

What the installer does not touch

The installer does not remove, adopt, or reconfigure unrelated containers, volumes, images, or Compose projects. Application data is never removed by an ordinary install, update, or uninstall.

Uninstall preview

sudo bash install.sh --uninstall

This prints what would be removed and stops without changing the host. Add --apply to remove the control plane and disable its boot services. The proxy, application containers, certificates, application data, Shipper metadata, and Docker are preserved.

For a full removal, see Uninstall.