Watchtower

Watchtower is a container registry monitor and image update automator that functions as a background service. It tracks remote image registries for changes to trigger the automatic deployment of updated Docker containers.

The tool manages the container lifecycle by monitoring for new base images and automatically executing the pull and restart sequence. It ensures that running containers are updated to the latest version available in the registry while maintaining original runtime configurations.

The system employs a polling event loop and digest-based change detection to identify updates. It uses configuration-driven filtering via environment variables and labels to determine which specific containers are monitored.

Features

Automated Container Image Updaters - Monitors registries for new image versions and automatically restarts containers to apply updates.
Daemon Unix Socket Communication - Communicates with the local Docker daemon via a Unix socket to manage image pulling and container lifecycles.
Image-to-Container Transition Management - Manages the transition from a newly pushed image in a registry to a running container instance.
Automatic Container Restarts - Automatically restarts containers using original runtime configurations after pulling newer base images.
Registry Monitoring - Periodically tracks remote image registries for new digests to trigger automatic deployment workflows.
Docker Container Lifecycle Automation - Automates the pull and restart sequence of Docker containers when newer image versions are available.
Docker Container Update Automation - Automatically updates running Docker containers when new base images are pushed to a remote registry.
Container Image Digest Comparisons - Compares unique SHA-256 image digest hashes from registries against local image IDs to detect updates.
Running Container State Tracking - Maintains a local record of running containers and their current image versions to identify necessary updates.
Continuous Deployment - Ensures the latest version of a container image is always deployed to production or staging environments.
Environment-Driven Feature Configurations - Uses environment variables and labels to define which specific containers are monitored and updated.
Self-Hosted Application Maintenance - Keeps self-hosted server applications up to date without manual intervention by automating image pulls and restarts.
Container Management Tools - Automated updates for running containers.

Star history

v2tecwatchtowerArchived

Name: v2tec/watchtower
Author: v2tec

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24,641 stars1,141 forksGoApache-2.05 viewscontainrrr.dev/watchtower

Watchtower

Features

Automated Container Image Updaters - Monitors registries for new image versions and automatically restarts containers to apply updates.
Daemon Unix Socket Communication - Communicates with the local Docker daemon via a Unix socket to manage image pulling and container lifecycles.
Image-to-Container Transition Management - Manages the transition from a newly pushed image in a registry to a running container instance.
Automatic Container Restarts - Automatically restarts containers using original runtime configurations after pulling newer base images.
Registry Monitoring - Periodically tracks remote image registries for new digests to trigger automatic deployment workflows.
Docker Container Lifecycle Automation - Automates the pull and restart sequence of Docker containers when newer image versions are available.
Docker Container Update Automation - Automatically updates running Docker containers when new base images are pushed to a remote registry.
Container Image Digest Comparisons - Compares unique SHA-256 image digest hashes from registries against local image IDs to detect updates.
Running Container State Tracking - Maintains a local record of running containers and their current image versions to identify necessary updates.
Continuous Deployment - Ensures the latest version of a container image is always deployed to production or staging environments.
Environment-Driven Feature Configurations - Uses environment variables and labels to define which specific containers are monitored and updated.
Self-Hosted Application Maintenance - Keeps self-hosted server applications up to date without manual intervention by automating image pulls and restarts.
Container Management Tools - Automated updates for running containers.

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Frequently asked questions

What does v2tec/watchtower do?

What are the main features of v2tec/watchtower?

The main features of v2tec/watchtower are: Automated Container Image Updaters, Daemon Unix Socket Communication, Image-to-Container Transition Management, Automatic Container Restarts, Registry Monitoring, Docker Container Lifecycle Automation, Docker Container Update Automation, Container Image Digest Comparisons.

What are some open-source alternatives to v2tec/watchtower?

Open-source alternatives to v2tec/watchtower include: getwud/wud — Wud is a self-hosted container image update monitoring system that periodically checks running containers against… nicholas-fedor/watchtower — Watchtower is a Docker container update automator that monitors registries for new image pushes and automatically… argoproj-labs/argocd-image-updater — Argo CD Image Updater is a tool designed to automate the lifecycle of container images within Kubernetes environments.… crazy-max/diun — diun is a monitoring service that tracks container registries for new tags or digest changes to notify users when… awslabs/aws-sam-local — aws-sam-local is a Docker-based emulator used for running and debugging AWS Lambda functions and API Gateway… mesosphere/marathon — Marathon is an Apache Mesos container orchestrator and distributed workload manager. It serves as a framework for…