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neilellis

It was cut and paste actually.

https://www.dropbox.com/s/lw1s0ip52do2r2v/Screenshot%202014-...

Not really selective, the concept is repeated more than once in the article. Honestly it's a bit misleading.

"Docker containers are restricted to a single application by design."

https://www.dropbox.com/s/a8843otngrhrp9x/Screenshot%202014-...

No they're not __restricted__ at all, you can certainly run multiple apps in a single container.

It is accurate to say Docker is focussed on the deployment of a single app per container. But the article does repeat it that it is single process.

The difference to be honest has really got thing to do with what you can do but what your aim is.

You can put sshd in your docker container, you can run init scripts. All these things are perfectly easy to do. It's just as a rule that's not your focus when working with Docker.

Again I think the article is misleading in this way.

IMHO of course ;-)

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Hmm, thought for sure I'd searched your exactly quote, but I apologize that I missed it.

It seems the author of the article in question replied to my comment as well, and it's worth noting because his intent is (more or less) what I got out of reading the post [1]. I don't find it misleading. I think your point of contention may therefore be with the interchange between application and process as synonyms throughout the post. By implication, I took it to mean application in the context of a single cohesive unit (maybe not just simply a process, though it can be) that is run via a supervisor or alone.

(That said, using LXC directly is something of an exercise in frustration as the CLI tools are a bit... kludgy--Docker is far more polished.)

> You can put sshd in your docker container, you can run init scripts.

I seem to recall that running sshd from a Docker instance isn't exactly the intended use case of Docker [2] and is generally frowned upon.

[1] https://news.ycombinator.com/item?id=8310276

[2] http://jpetazzo.github.io/2014/06/23/docker-ssh-considered-e...

Hi Zancarius, my apologies, I mistakenly replied to you when it was intended for neilellis.

Imho if your use case is not statelessness and you need a container as a lightweight VM, LXC tools are actually quite simple and easy to use.

Nielellis - I am sorry you feel the article is misleading. It describes the default behavior. The default Docker template has limitations, that the user should be aware or you get questions like this - http://stackoverflow.com/questions/21280174/docker-centos-im...

I would suggest you have a look at rationale for Phusion base image here - http://phusion.github.io/baseimage-docker/

Docker base template is not a multi process multi app environment, it executes the application specified on the docker command line and exits. Which is why you can't run apps in daemon mode and have to explicitly disabled, and need a separate process manager.

Agreed. I think it might be more accurate to say that Docker containers have a philosophy toward individual applications within a container.

But those applications could have multiple executables, services, processes, etc...

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