[rid]

I'm surprised they haven't included a process manager for the production build. In my experience it allows for much easier 0-sec downtime updates and load balancing.

We're using pm2 [1] for this if anyone's interested.

[1] https://github.com/Unitech/pm2

[alberteinstein]

If you use container orchestration platforms like Kubernetes, this is not required, as restarts load balancing etc. are handled by the orchestrator.

[rid]

Does Kubernetes support graceful reload of containers, with 0 downtime? I'd be very interested if so.

[alberteinstein]

Yes, it does. Kubernetes can perform rolling updates [1].

One scenario is that when you rollout a new version, the old container will only be killed when new one is up and running. If there are many replicas running, Kubernetes will replace them with new versions one by one. And all of this behaviour is highly configurable.

[1] https://kubernetes.io/docs/tutorials/kubernetes-basics/updat...

[rid]

Thanks! I think for our scenario it's a bit overkill as we're only running one container and pm2 seems a better fit for that.

It would be interesting to know how this works under the hood though, is this just built on top of docker swarm load balancing?

[alberteinstein]

Kubernetes will definitely be an overkill if you run only one container. But, if your application follows microservice architecture and have multiple containers, Kubernetes is the best solution to run them.

Kubernetes architecture is entirely different from that of Docker Swarm.

A Kubernetes Service object [1] can load balance traffic to various Kubernetes Pods (think containers) [2] as defined by it's " pod selectors". It can choose to direct traffic only to running containers.

[1] https://kubernetes.io/docs/concepts/services-networking/serv... [2] https://kubernetes.io/docs/concepts/workloads/pods/pod/

[tango12]

It does. Look at https://kubernetes.io/docs/concepts/workloads/controllers/de...