Breaking Free From the Cloud With Mrsk: Just Enough Orchestration for Your Apps

There is no doubt that the cloud has changed the way we run our software. Startups, for instance, can get started without buying expensive hardware and scale flexibly. Also, the cloud has enabled novel solutions such as serverless, managed Kubernetes and Docker, or edge functions. For a time, cloud-native applications seemed to be the way forward for most teams, big or small.

But in exchange for all this power, we pay a cost. And it can be a steep one. 37signals — the company behind HEY.com and Basecamp.com — has calculated that by buying a few servers and moving from the cloud to on-premise, they can save 7 million dollars over 5 years.

And it is not an isolated case. Recently, Amazon Prime — the poster child of serverless architectures — moved part of its infrastructure from serverless into a monolith and cut costs by 90%.

Does this mean that we should we go back to bare metal servers like in the old days? Not quite. We can still enjoy many of the benefits of the cloud, like horizontal scalability and no-outage upgrades using containers in combination with an orchestration platform. On that note, 37signals recently released MRSK, a tool that allowed them to to completely leave the cloud, saving them money and improving performance for their users.

What is MRSK?

MRSK (Manage Remote Server Kontainers) is a deployment tool for containerized applications. It uses Docker containers to run the software and Traefik, a reverse proxy and load manager, to perform rolling updates.

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MRSK keeps things simple by:

• Using standard Docker images.
• Connecting to the servers via SSH.
• Giving each server a single role.

The last point gives us the first clue about how MRSK works. It assumes a multi-server setup, where every machine fulfills only one role. In other words, if your application requires a database, MRSK expects to have at least two servers: one for the application and one for the database.

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MRSK cares about your servers and little else. Load balancing is limited to the server level. MRSK uses Traefik to forward HTTP traffic to every container running on a machine. If you want to do horizontal scaling, you’ll need to put a separate load balancer in front of everything.

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Because MRSK doesn’t care where the application runs. You can use a cloud server, on-premise machines, or even run VMs on your laptop to test drive the tool.

Getting started with MRSK

You’ll need the following to build and deploy an application with MRSK:

Originally published at https://semaphoreci.com on June 29, 2023.