Updating Docker Containers
Tags: Docker
Note: Written with the help of my research team 🙂 including: (Google Gemini, Google Notebook LM, Microsoft Copilot, Perplexity.ai, Claude.ai and others as needed)
You can manage many devices using docker remotely with Portainer. However Portainer does not have the ability to check if there are updates and actually update containers within Docker. Up until a few months ago, there was a script which I have used for years to do this called: watchtower. Unfortunately, watchtower is not being maintained any longer, and although it still works, many do not use it because of its inactive status. Are there other choices?
See my related post Portainer Agent on Windows: Fixing LAN Access
Current Open-Source Alternatives to Watchtower
| App Name | Primary Function | Most Recent Activity Date | Status |
Watchtower (Official) (containrrr/watchtower) | Auto-Update (Container) | ~2022 (Last Major Release) | Inactive (Project considered unmaintained by community members. May have issues with modern Docker API versions.) |
Watchtower Fork (nickfedor/watchtower) | Auto-Update (Container) | Nov 13, 2025 (Recent Commit/Activity) | Active Fork (Directly addresses the maintenance gap of the original project.) |
| WUD (What’s Up Docker) | Auto-Update & Notify (GUI) | Nov 26, 2025 (Recent Commit/Activity) | Very Active (Modern GUI alternative.) |
Dockcheck (mag37/dockcheck) | Auto-Update & Notify (CLI) | Oct 6, 2025 (v0.7.3 Release) | Very Active (Robust CLI with Prometheus support.) |
Container Updater (brutaldev/ContainerUpdater) | Auto-Update (CLI) | Last Week (Latest Commit) | Very Active (Non-container-based, focuses on simplicity.) |
Renovate Bot (renovatebot/renovate) | Notification (GitOps PRs) | Nov 18, 2025 (Renovate v42 Update) | Very Active (The GitOps approach to updating dependencies.) |
Diun (crazy-max/diun) | Notification Only | May 5, 2023 (Recent Mention/Use) | Active/Stable (Focuses purely on lightweight notifications.) |
The most popular open-source choices that serve as alternatives or successors to the original Watchtower include:
Top Actively Maintained Alternatives
| App Name | Primary Function | Interface | Key Advantage |
| What’s Up Docker (WUD) | Auto-Update & Notify | Web UI (GUI) | Offers a complete, easy-to-use GUI for monitoring multiple hosts and performing updates with a click. |
| Diun (Docker Image Update Notifier) | Notification Only | Notification Service | Very lightweight, focuses solely on notifying you via numerous channels, leaving the update to you (safer for complex stacks). |
| Dockcheck | Auto-Update & Notify | CLI / Scheduled Cron | Excellent CLI tool with interactive mode, update delay features, and Prometheus metrics support. |
Honorable mentions:
These tools go beyond simple image checking and integrate with larger GitOps or management workflows:
- Komodo (mbecker20/komodo)
- Focus: It’s more of a full-stack container manager (like a Portainer alternative) that includes automated update functionality for your Docker Stacks.
- Advantage: Useful if you want a complete management GUI that integrates updates and stack deployment.
- Container Updater (brutaldev/ContainerUpdater)
- Focus: A
.NET Core Global Toolto automate updates. It’s often run manually or via a script/cron job. - Advantage: Supports an interactive mode, remote host connections, and is compatible with existing Watchtower labels. It emphasizes simplicity without running as a Docker container itself.
- Focus: A
- Renovate Bot (renovatebot/renovate)
- Focus: Not a direct Watchtower replacement, but a modern GitOps approach. It scans your
docker-compose.ymlfiles (or other dependency files) in a Git repository. - Advantage: When a new image is found, it automatically creates a Pull Request (PR) on GitHub/GitLab with the updated version tag. You merge the PR to update the tag, and your deployment system (like Komodo or a CI/CD pipeline) then handles the container deployment. This gives you full version control and approval before deployment.
- Focus: Not a direct Watchtower replacement, but a modern GitOps approach. It scans your
- nickfedor/watchtower
- Focus: A direct fork of the original project.
- Advantage: This image is often cited by users as a drop-in replacement that has been updated to fix the compatibility issues (specifically, the old Docker API version error) encountered with the official
containrrr/watchtowerimage on modern Docker Engine releases (like v28+).
Key Considerations for Top Docker Update Tools
| Feature | WUD (What’s Up Docker) | Diun (Docker Image Update Notifier) | dockcheck (mag37/dockcheck) | nickfedor/watchtower (Fork) |
| Primary Function | Auto-Update & Notify | Notification Only | Auto-Update & Notify | Auto-Update Only |
| Interface | Web GUI | Notification Service | CLI/Script-based | Background Container |
| Automatic Updates | Yes, with triggers you define. | No, notifications only. | Yes, with interactive or automatic mode. | Yes, fully automated. |
| Update Granularity | Full image/stack update. | None (user performs update). | Selective Updates (choose which container). | All or Selected via Labels/Names. |
| Key Advantage | Easiest-to-use Web Interface. | Lightweight and safest for production. | Interactive CLI and Prometheus metrics. | Drop-in replacement for original Watchtower. |
| GitHub Activity Status | Very Active Last Update: Nov 26, 2025 | Very Active Last Update: Oct 26, 2025 | Very Active Last Update: Nov 13, 2025 |
Summary Comparison:
- If you just want Watchtower to work again: Choose the
nickfedor/watchtowerfork. - If you want a modern Web Dashboard: Choose WUD.
- If you are CLI-focused and want interactive/selective updates: Choose Dockcheck.
- If you only want a safe, hands-off notification system: Choose Diun.
Hope this helps!
Disclaimer: I work for Dell Technology Services as a Workforce Transformation Solutions Principal. It is my passion to help guide organizations through the current technology transition specifically as it relates to Workforce Transformation. Visit Dell Technologies site for more information. Opinions are my own and not the views of my employer.