Yesterday I was at a conference dedicated to DevOps and so Red Hat and Google were there to talk about containers, especially Docker and Kubernetes. While summarizing it to some of my employees today, I was asked about what I see as the benefits of Docker containers relative to Virtual Machines. I mentioned that one of the great things is that Docker containers are immutable. All of your data’s actually written to a folder that’s essentially mounted in the container.
Then today while I was walking through the neighborhood with Stella I was thinking about that and suddenly into my head popped a reddit discussion I had with someone on /r/Datahoarders. This person had a bunch of computer OS backups with his data intermingled. I mentioned he was doing things wrong – he should have his data on a data drive or in a NAS, separate from the OS so that he doesn’t need OS backups, only backups of settings and his personal files. On my Linux computer I do this by having a separate home drive. On my Windows computer I’ve mapped “My Documents” to a separate drive.
And the lightbulb went off. Right now with my VMs, I’m backing up an entire VM, taking up gigabytes of space and taking lots of time to back up. Instead, with Docker containers I could merely worry about backing up the data store. The containers themselves don’t matter because I can always just grab them again off the repos.
So it looks like it’s time for me to learn OpenShift (since I’m all-in for Red Hat, I may as well learn their distro of Kubernetes) so I can better orchestrate all of this now that I’m moving from just a couple containers. Plus it’ll be fun to learn!