[toomuchtodo]

We bake the container into the AMI, so no fetch is necessary at spin up (there is no cost to generate AMIs, only storage fees, so cost is not an issue).

Packer is used to build the AMIs with the containers built-in, and Docker is used both in Prod (single container to each AMI) and Dev (Docker Compose to bring up entire dev env locally). Both used a shared docker registry.

[eropple]

Ahh, gotcha. That's a neat approach, though the double hit of Docker builds + AMI builds feels a little weird to me. Thanks for the insight.

[Leon]

I also do what the other poster does, but we take it a step further and make sure that the layers on the image have smaller and more variable layers near the last layer add. On instance startup we can do a docker pull and bring down only a few k of bytes for docker image updates. This way we can update the ami less often (which it takes longer anyway) and we don't worry too much about pushing updates to the container repo without having to batch ami builds for quicker turn around deployment.

[toomuchtodo]

If you're in AWS, I wouldn't worry about how many bytes docker image updates take. Our registry is using S3 as its backend, and I can pull images under 100MB in a few seconds.

[Leon]

It's not always an option to host and manage a registry, some parts it's easier for the customers to rely on a registry service like quay, in which case it can make a difference for some images to think about layering. But you are right, s3 is fast and that's one of the reasons I'm glad Deis moved to support s3 out of the box.