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Show HN: Unregistry – “docker push” directly to servers without a registry

(github.com)
726 points psviderski | 1 comments | 18 Jun 25 23:17 UTC | HN request time: 0.209s | source

I got tired of the push-to-registry/pull-from-registry dance every time I needed to deploy a Docker image.

In certain cases, using a full-fledged external (or even local) registry is annoying overhead. And if you think about it, there's already a form of registry present on any of your Docker-enabled hosts — the Docker's own image storage.

So I built Unregistry [1] that exposes Docker's (containerd) image storage through a standard registry API. It adds a `docker pussh` command that pushes images directly to remote Docker daemons over SSH. It transfers only the missing layers, making it fast and efficient.

  docker pussh myapp:latest user@server
Under the hood, it starts a temporary unregistry container on the remote host, pushes to it through an SSH tunnel, and cleans up when done.

I've built it as a byproduct while working on Uncloud [2], a tool for deploying containers across a network of Docker hosts, and figured it'd be useful as a standalone project.

Would love to hear your thoughts and use cases!

[1]: https://github.com/psviderski/unregistry

[2]: https://github.com/psviderski/uncloud

Show context
revicon ◴[19 Jun 25 15:29 UTC] No.44319604[source]▶
Is this different from using a remote docker context?

My workflow in my homelab is to create a remote docker context like this...

(from my local development machine)

> docker context create mylinuxserver --docker "host=ssh://revicon@192.168.50.70"

Then I can do...

> docker context use mylinuxserver

> docker compose build

> docker compose up -d

And all the images contained in my docker-compose.yml file are built, deployed and running in my remote linux server.

No fuss, registry, no extra applications needed.

Way simpler than using docker swarm, Kubernetes or whatever. Maybe I'm missing something that @psviderski is doing that I don't get with my method.

replies(2): >>44319744 #>>44321814 #
1. tontony ◴[19 Jun 25 19:36 UTC] No.44321814[source]▶
Totally valid approach if that works for you, the docker context feature is indeed nice.

But if we're talking about hosts that run production-like workloads, using them to perform potentially cpu-/io-intensive build processes might be undesirable. A dedicated build host and context can help mitigate this, but then you again face the challenge of transferring the built images to the production machine, that's where the unregistry approach should help.