Docker: Explore option for zero-downtime deployment

[jpmckinney]

e.g. blue-green deployment

This can be done with elaborate systems like Kubernetes or Rancher, but it's also possible to do it by simply scaling new/old versions of containers up/down (see links below).

Preference is to do it via scaling.

I think we would have to change how we do networking for Docker containers. Right now we assign individual ports to containers.

In the blog posts, https://github.com/nginx-proxy/nginx-proxy or Traefik (which has Docker support) are used, to (as I understand) autodiscover the ports instead.

Similar:

• https://github.com/Wowu/docker-rollout
• https://www.tines.com/blog/simple-zero-downtime-deploys-with-nginx-and-docker-compose/
• https://linuxhandbook.com/update-docker-container-zero-downtime/
• https://blog.slava.dev/zero-downtime-deployment-with-docker-d9ef54e48c4
• https://www.maxcountryman.com/articles/zero-downtime-deployments-with-docker-compose

[jpmckinney]

There's also dokku and https://kamal-deploy.org but I think a simple configuration as above might be better.

[jpmckinney]

Another option is k3s.