My intro to Docker - Part 5 of something

In the previous posts, I have talked about everything from what Docker is, to how you can set up a stack of containers using docker-compose, but all of the posts have been about setting up containers on a single machine. Something that can be really useful, but imagine being able to deploy your containers just as easily to a cluster of machines. That would be awesome!

With Docker Swarm, this is exactly what you can do. You can set up a cluster of Docker hosts, and deploy your containers to them in much the same way that you would deploy to a single machine. How cool is that!

Creating a cluster, or swarm

To be able to try out what it’s like working with a cluster of machines, we need a cluster of machines. and by default, Docker for Windows/Mac includes only a single Docker host when it’s installed. However, it also comes with a tool called docker-machine that can be used to create more hosts very easily.

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My intro to Docker - Part 4 of something

In the previous posts about Docker, here, here and here, we’ve looked at what Docker is, how to set up a basic container and how to set up a stack of containers using docker-compose. One thing we haven’t talked about is the fact that most projects use some form of persistent data store, and the most common store, at least in my world, is a relational database of some sort. So this time, I want to cover something that might seem slightly odd…setting up an MS SQL Server…on Linux…in Docker.

Yes, you heard me right… I’m going to show you how to set up an MS SQL Server instance in a Linux-based Docker container. Something that wouldn’t have been possible, in any way, not too long ago, but Microsoft “recently” released a version of MS SQL Server that runs on Linux, which is really cool. And running it in Docker just makes sense!

Running MS SQL Server in a Docker container

Starting a SQL Server instance in a Docker isn’t that hard, but there are a couple of things that need to be set up for it to work.

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My intro to Docker - Part 3 of something

So far in this little blog series about Docker, I have covered what Docker is, how it works, how to get a container up and running using pre-built images, as well as your own images. But so far, it has all been about setting up a single container with some form of application running inside it. What if we have a more complicated scenario? What if we have a couple of different things we want to run together? Maybe we want to run our ASP.NET Core app that we built in the previous post behind an nginx instance instead of exposing the Kestrel server to the internet… Well, obviously Docker has us covered.

However, before we go any further, I just want to mention that I will only be covering something called docker-compose in this post. This can be used to create a stack of containers that are set started and stopped together. I will not be covering distributing the application accross several nodes this time. There will be more about that later. And even if that is probably the end goal in a lot of cases, being able to just run on a single host can be useful as well. Especially while developing stuff.

What is docker-compose?

When you installed Docker for Windows or Docker for Mac, you automatically got some extra tools installed. One of them is docker-compose, which is a tool for setting up several containers together in a stack, while configuring their network etc. Basically setting up and configuring a set of containers/apps that work together.

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My intro to Docker - Part 2 of something

In the previous post, I talked a bit about what Docker is, how it works, and so on. And I even got to the point of showing how you can create and start containers using existing images from Docker Hub. However, just downloading images and running containers like that, is not very useful. Sure, as a Microsoft dev, it's kind of cool to start up a Linux container and try out some leet Linux commands in bash. But other than that it is a little limiting. So I thought I would have a look at the next steps involved in making this and actually useful thing…

Creating something to host in a container

The first step in using Docker is to have something that should run inside of our containers. And since I am a .NET developer, and .NET Core has Linux support, I thought I would write a small ASP.NET Core application to run in my container.

Note: Before you can run this, you need to install the .NET Core SDK

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My intro to Docker - Part 1 of something

It’s been quite a while since I blogged, and there are several reasons for this. First of all, I haven’t really had the time, but I also haven’t really found a topic that I feel passionate enough about to blog about. But having played around with Docker, I now have! So I thought I would jot down some stuff about Docker… If nothing else, it gives me a away to come back to what I used to know when I have forgotten all of it again…

What is Docker?

The first thing to cover is what Docker really is. I have seen a lot of explanations, both of what it is, and why it is so good. But I have had a hard time grasping it in the way that it has been explained to me. So here is my explanation. And by my explanation, I mean the way I think about it. It might not be 100% correct from an implementation point of view, but it is the way I see it…

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