August 31, 2017

Use Ansible to apply rolling updates to Docker swarm nodes

Even with all those elastic superscaling whatsoever buzzword stuff, sometimes it just comes down to simple upgrading a component like Docker daemon itself or a new kernel. With swarm, this means draining the node, do our stuff, probably reboot and then set it active again. Being ephemeral is cool, so we could spawn new (updated) swarm members using Ansible and then destroy the old hard-working bees afterwards. But to me, this seems more like a “just because we can”, even more then running small or medium sized swarms/clusters. Read more

March 17, 2017

Deploy to Docker Swarm using Gitlab CI

UPDATE 2017-06-07: Added info about secure connections You might have heard of awesome Gitlab and it’s builtin CI. Also, Docker might ring some bells. And Gitlab loves Docker. I’m using Gitlab CI with Docker for a long time now, even before Gitlab included the container registry. Playing around with Swarm some months ago immediately made me want to combine all of them. The whole Kubernetes thing is pretty cool but sometimes just too much. Your Dev’s probably rather want to code instead of playing DevOp or Sysadmin. Also i must admit that running Docker swarm is much easier than running a full blown Kubernetes stack. And Docker commands in swarm mode are almost the same, so hurdles for developers are almost gone if they are already using Docker ;) Read more