I'm currently a senior in computer science and I've landed a DevOps internship that requires a solid understanding of Docker, which has been a bit daunting. I've installed Docker and gone through some basic documentation, but I'm still a little confused about its purposes beyond just creating isolated environments to run applications. Specifically, I'm curious about how Docker containers differ from traditional virtual machines when it comes to testing and running applications. Would really appreciate any insights!
3 Answers
Two main advantages of using containers are that they ensure you have the correct dependencies and allow you to run multiple applications with conflicting dependencies on a single host. You can achieve this with VMs too, but it often requires spinning up multiple instances, which can waste resources.
Think of it like this: VMs virtualize the hardware, while Docker containerizes the software. I've found using Docker Compose really helps in setting up environments, as it gives you a solid base for your applications.
Containers are much lighter than virtual machines, which makes them super quick to start up and shut down. To recreate a container, you only need a Dockerfile and some run parameters, while with a VM, you'd need a whole operating system image.
Exactly! This lightweight nature makes Docker a favorite for many developers.
That’s a great tip! Docker Compose takes a lot of the headache out of managing multi-container applications.