Docker in RHEL/CentOS 8

rhel8-docker-install.txt

Assistance from this article: https://www.liquidweb.com/kb/how-to-install-docker-on-centos-8/
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Introduction
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Red Hat and Docker broke up which means you can't just install Docker in CentOS or RHEL 8 and expect it to work.
In fact if you follow the docker instructions to install, you *will* get some of docker installed but when you try to start the service it will bomb.

So how do we get around this?  Trick yum (or dfn) into thinking we're running release 7. Then install Docker and Docker Compose.
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Procedure
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Add Docker repo
  dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo
  
Edit docker-ce.repo to change version
  vi /etc/yum.repos.d/docker-ce.repo

Search for the "Docker CE Stable" block and change the baseurl value
  baseurl=https://download.docker.com/linux/centos/7/x86_64/stable/
  
Confirm you have packages for version 7
  dnf list docker-ce
  
Install Docker with last good package
  dnf install docker-ce --nobest
  
Confirm Docker installed
  docker -v
  
Launch Docker
  systemctl enable --now docker
  
Confirm install
  systemctl status docker
  
Add user(s) to docker group
  usermod -aG docker root
  
Confirm your user is in the correct group  
  id root
  
Test Docker (note: you may need to logout for your user's group assignment to take effect)
  docker run hello-world
  
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Addendum 01: FirewallD (the D stands for "Die, Docker, Die!"
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While I haven't run into this issue using RHEL8 AMI in AWS, many users report that RHEL/CentOS 8 firewall blocks traffic within the cluster (specifically DNS lookups).

Disable the system firewall to cleanup that behavior
  systemctl disable firewalld

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Addendum 02: Docker Compose
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So you want docker-compose to work?  Get ready to install it manually.
  curl -L "https://github.com/docker/compose/releases/download/1.25.0/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

Make your newest toy executable
  chmod +x /usr/local/bin/docker-compose
  
Floss your new whip
  docker-compose -v