alvinchow86

I'm curious about what kind of scalability challenges you had in mind?

Appreciate the comment. The point I was hoping to get across wasn't that Docker would completely replace CM (or that CM is a bad thing), but that it could help reduce the amount of work in the CM world. As mentioned, we still needed to use Chef anyway (and using Opsworks to get a head start), so at least in this kind of environment CM is still necessary. That said I can see how the article could be slightly misleading =)

Yup, pretty much.

We actually were using Docker Hub but they went down a few times so we are going to try setting up a private registry. We also tried Docker Hub's "Automated Build" service but it doesn't do any layer caching between builds so we found it way too slow.

One thing I'd recommend is at least installing the Docker service itself on the AMI (spinning up EC2 instances, especially on Opsworks, is slow enough as is)

Good question - I did take a brief look but it wasn't really solving the main problem we had at the time, which was how to manage a cluster of servers. I feel like emulating the Heroku features is pretty easy to do yourself anyway (and kind of a fun exercise)

As skwirl pointed out, yes SSHing is more for debugging production server issues than for setting up the servers.

The transition itself took one month. So far it's been several months and it's been very stable with pretty minimal maintenance. We did end up writing a number of Python scripts to help make the deploy process easy for developers (i.e. replicating most of the common Heroku features we used to use)