A few days ago the boys of Resin.io we were literally left speechless at the idea of creating a cluster made up of no less than 144 Raspberry Pi. With this in mind, surely it will have happened to you like me, it occurred to me to search through all kinds of forums and repositories how create our own cluster, with fewer units, but in a simple way to learn much more about this architecture and all that it can offer us.
For those who are not very clear about what I am talking about, the idea in general lines is to create our own cluster, that is, interconnect several computers, in our case several Raspberry Pi, so that they work as if it were only one. After spending a lot of time researching, at least in my case, it seems much easier if we opt for the platform Docker.
Alex Ellies shows us how to create our own cluster composed of several Raspberry Pi.
At this point, mention that the first thing we should have is a few Raspberry Pi and for this, in case we do not want to spend too much money, especially for something we do 'for learning', will be to look at the second-hand market and get a few at an affordable price. Once we have several we will get down to business even though, as is my case, have never set up a cluster although I have seen several working.
With this in mind and so that we all have it much clearer, I want to base all the work on the tutorial that at the time published Alex Ellies on Youtube where he teaches us how to configure several Raspberry Pi, in his case no less than 7 units, using for this the one known as'Swarm Mode'from the Dockers platform. To carry out this, the first thing is to have Raspbian reinstalled on the memory cards of each Raspberry Pi to later be able to install Docker 1.12. For all this you have information both in the video and in the Alex Ellis's own blog.