Scaling Docker #2 - Tutorial on Scheduling Docker Containers across CoreOS machine with Fleet

Now that we've built a CoreOS cluster, let's schedule apps across it with Fleet.

- Cluster computing - CoreOS is our solution here. CoreOS allows us to make an expandable cluster of computers so we can add more computers should our application need more power to scale. CoreOS also allows us to run services on any machine in the cluster and they can all communicate with each other.

THIS VIDEO:
- Scheduling: we shouldn't manually choose which app runs on which machine - this idea doesn't work at scale. Fleet will be our scheduler that decides where our apps/services run. If a CoreOS machine goes down, fleet will reschedule any services that it was running onto a new machine.

- Service Registration/Service Discovery: Since we never know what ip address or port a service will be running on, we need to register that service so other services can find it and communicate with it. We'll use Etcd and Flannel for this

- Public DNS: Once the app is working, we need a fixed way for the outside world to access it. We'll use Nginx and Confd for this. Confd will watch Etcd for service registration and when services come/go, it will build a new configuration file for Nginx and reload Nginx.

This docker tutorial will help you understand how to go through every step of this process.

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[JoshuaKersey]

This was a pretty good video and covered a lot of info. For anyone else watching that has to check the status of services as they start, I recommend using the watch command. To install watch on OSX you can use "brew install watch" if you use homebrew. You can add "-n 1 -d" to run the fleetctl command every second and highlight differences between executions.

[iliyass]

awesome, i really needed this type of videos about docker, i think if you are not using docker this way, you are just wasting time and effort !!

[pgtrots]

@ is 'at' symbol.
Ampersand is &.


Great videos though, can't wait for 3 4 5!

[ctrlbrk]

Fantastic series. However, can you update this example but since fleet is deprecated, can you do it with Kubernetes instead?

[matthewfieldhouse]

"For numerous technical and market reasons, Kubernetes is the best tool for managing and automating container infrastructure at massive scale.

To this end, CoreOS will remove fleet from Container Linux on February 1, 2018, and support for fleet will end at that time."

[bmfitzgerald]

Hey Will, thanks for this interesting content. I'm following along w/ this approach and I also followed along in another video when you used nginx as a front-end to a cluster. Any specific reason to choose the (what apperas to be simpler) nginx/cluster approach to horizontal scaling vs. this (more advanced?) CoreOS approach?

[MrInexistent]

I watch two of the videos. Very helpful in general understanding. How did you create those files though. Are they auto-generated by a script? Also syntax was very similar with ansible.

[likku]

Nice Video.I have a small doubt is it possible to use the fleetctl commands from a Windows machine.If Yes, Please let me know the procedure.

[ZigzagKazak]

Again, awsome tutorials. I do have a question, I followed your tut and when I browsed your sample-node (name was updated) I get "ok" on the browser and not "someapp1". Did I do something wrong, or have you updated the project?
tnx again