(Update 02-04-2019) What Is Container Orchestration? (by Isaac Eldridge at New Relic).
I also followed along the Exploring Docker  – Getting Started by Traversy Media. I did make the node.js and MongoDB work on my local MacBook, but I could not make them working on my DigitalOcean droplet due to mismatch of Docker versions of “Docker Compose”, the root cause was the Ubuntu on my Droplet was a a bit old (14.0.4). I need to upgrade it to make the versions compatible.
(Update 02-13-2018) So I found out today I have AWS bill of $2.62 (mostly due to EC2 instances) today. This is due to the fact that I did fire up the VM as well as the docker swarm instances (total 9? maybe due to I ran the deploy script multiple times?) Anyway I fired up the instance last night, this evening I looked at the “instances” and looked at the bill, I know what happened. I still did not make the connection from outside to ec2 working though. For the time being, I “terminated” the docker swarm, and stopped AWS VM.
(Update 02-12-2018) I am also following the tutorial at Docker’s official website. I am at step 6 here. And right now, I am stuck in connecting to the AWS vm (was following this Docker guide): step 6 “docker node ls”. I did follow the steps to create docker credentials for AWS.
error during connect: Get https://192.168.99.102:32768/v1.35/nodes: http: server gave HTTP response to HTTPS client
Note this IP address looks like the local default machine: one thing I am not quite sure is how the local connects AWS
(Original 01-31-2018) I installed docker on my mac a while ago and did a simple tutorial. But I never had much chance to play with it until recently. After the training, esp. after I saw use docker container to host Tomcat, and then use Jenkins to startup Tomcat (build and deployment), this whole thing got me interested in docker again. Note I have been learning about docker contain and they seem to be the future deployment model for scalable mobile apps backend: e.g., I know the Robinhood app (the free stock trading app) is container based in the back.
Some resources I used to get started:
1) Youtube docker tutorials (11-18-2018: such as this one Demystify Docker; also noticed this one Docker for GCP. I will see if I can do the training exercise again I mentioned above).
2) Install docker or docker.io on Ubuntu (I have a digitalocean droplet / VM, and its OS is Utuntu);
3) Overcome the error message:
FATA Get http:///var/run/docker.sock/v1.17/version: dial unix /var/run/docker.sock
The answer is this:
The problem is that your user has not been added to the docker group.
sudo usermod -a -G docker
If you don’t want to log in/out from your current shell, run:
Last but not least, install Jenkins on Ubuntu 14.04.
Other error messages (note I am on a Mac)
Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running? (when I tried to run some docker command)
It seems the solution is
eval “$(docker-machine env default)”