Ongoing Investigations

Just using this space quickly to type up some thoughts about Week 1 of the containers workshop we hosted in July. For a variety of reasons I’m only now getting the opportunity to work through the exercises, one week at a time, so here we go.

Week 1 covered an introduction to containers: what they are, why they’re useful, where the idea comes from, and how to get started. Jim likened digital containers, which I often reductively describe as “scalable micro-servers”, to real-life shipping containers: a way to package a specific thing or set of things (in this case, softwares) in a way that keeps them isolated and secure, that standardizes how things are organized, that keeps them flexible and easy to rearrange, and that reduces the cost of (in real life) shipping or (on the web) hosting.

Getting started meant going through the Reclaim Cloud interface, which I was already somewhat familiar with. We covered how to locate the Settings area, how to set up a new container using the marketplace, where that container and its nodes (component sub-containers) live, and how to access the settings, configuration, and terminal for a given node.

The exercise for the week was to set up a Docker container using the marketplace’s installer and then use the terminal to run the command docker run hello-world. The tutorial video also showed how to poke around inside the environment topology, how to find a given container’s settings and file manager, how to create new files and folders, and several other things.

This was a good combination refresher-intro — it helped me refamiliarize myself with tools I’d already used and understand a little more about how they work and what they’re made up of. It was also useful from a terminology standpoint, as that’s often where I’ve had issues in the past — while I can conceptualize things, understanding what a person or a tutorial is referring to with a given term can be really difficult for me.

Questions and Takeaways:

• I was still pretty unclear on what actually happened when I ran the docker run hello-world command. Something definitely ran, because the terminal printed out some introductory information, but when I navigated to the URL for my environment, I got an error that nothing was there.
• While the container can just run the command and stop, it’s still active in the background and using resources — so what’s it using them for, if it isn’t doing anything?
• How would I set up/program an environment to continue running indefinitely? I know it’s possible because that’s how Reclaim Cloud applications run, but I don’t know what I would need to do if I wanted to develop my own little application.
• For that matter, how would I build custom Docker images for those little applications?
• I need to review setting up SSH keys so that I can choose between the Reclaim Cloud terminal and my local terminal if I want.