What’s the Difference Between Docker Volumes and Copy/WORKDIR in a Dockerfile?

Here’s a quick breakdown: 1. COPY brings files in, 2. WORKDIR defines where in the image commands run, and 3. Volumes offer a place for data that stays around even when containers are shuffled around. Remember, images are like the blueprint, containers are the actual running thing, and volumes hold onto the stuff!

If you want to ship a container image with certain files permanently included, you'd use COPY in the Dockerfile to bake them right into the image. But if you want to make sure users can access or modify files, you'd use a volume, so they exist outside this image and can be adjusted as needed. That's where the big difference shines!

To put it simply: COPY is just bringing files into the image at build-time, and WORKDIR is just about setting where commands run inside that image. Volumes are for runtime and are linked to your host – they keep data safe even after a container stops, which is super handy for things like databases or any app needing persistent state.

Great question! COPY and WORKDIR are things you set in your Dockerfile for building the image itself. This means if you change anything later, those will reset to whatever your initial image was. But volumes are still there on the host system and can be reused across multiple containers. It's basically between what's effectively a snapshot versus dynamic storage!

They're actually quite different! Docker volumes are all about persistent storage and are used to keep your data even after containers shut down. This means if you start a new container with the same volume, your data remains intact. On the other hand, COPY and WORKDIR in a Dockerfile are used during the image build process; they don't hold onto any data after a container is recreated because those layers are immutable. So yeah, once you get that, the differences become clearer!