Can you suggest best resources (text/video) for learning about Kubernetes & Mesos? I use Docker & CoreOS all the time (love it) and I'm always trying to improve/learn something new. Can you tell how do you use Apache Aurora? What other interesting projects are worth learning about?
I recently spent some time playing with Mesos, Marathon (the web ui + api for scheduling long-running jobs / services) and Chronos (the web ui + api for scheduling cron / batch jobs).
I did this on my Macbook, using Virtualbox, Vagrant, and this:
Honest answer: I don't. In short: most of the things have fixed config that is loaded into etcd cluster and different services in Docker containers use it to communicate with other containers/services (something like {rabbitmq_host: "host address"}. In the project I'm working on right now I have just 10 boxes which will probably grow to 20-30 in the coming months. It's nothing, I know, and as you can tell from the hacky nature of my setup I'm learning as I go about this, but I'm trying to incrementally improve different parts. Something like Kubernetes/Mesos seems like a next step.
In case you're interested, the next version of Docker (1.7) supports multi-host networking and dynamic service discovery out of the box.
The whole thing is pluggable and can use various distributed state backends (etcd, zookeeper etc) or IP connectivity backends (veth, macvlan, vxlan, openvpn etc) without changing your application. Service discovery uses DNS so you don't need to modify your application to take advantage of it. It's probably the most significant change to Docker in the last year.
This will make the integration with Kubernetes smoother. Currently Google is forced to rip out Docker's native networking stack because it is not flexible enough for their opinionated networking model. This causes many Docker applications to break in Kubernetes today. That problem should go away with Docker 1.7+ because Google-style networking can be expressed as a Docker plugin, which Kubernetes can load programmatically as part of its orchestration. An added benefit is that you can augment Docker with Google-style networking even if you use Kubernetes competitors like Mesos, Swarm, Cloudfoundry etc.
Hi Solomon, do you have an ETA for Docker 1.7? I see that it's currently in RC1. How soon will we be able to take advantage of libnetwork via Compose? Is there any documentation yet on how it will be done in Compose? Is there currently an easy way to try it via Boot2Docker?
Sorry about the barrage of questions. As you can probably guess, I'm very interested in trying this out.
On a past project I did service discovery with Docker and CoreOS using SkyDNS with etcd. Services would register their network location in etcd and SkyDNS would translate those entries into DNS records. SkyDNS ran on every host and the app-level containers linked to the SkyDNS container.
If a container was moved across hosts, the etcd entry would be updated automatically and eventually the updated DNS entry for that service would propagate across the cluster.
