Run Docker without Sudo

Docker of old versions by default must run with 'sudo', do these to run as normal user (required that the user is in 'wheel' or 'sudo' group):

Optional: Install Docker if not yet
sudo yum install docker -y

Optional: Start Docker service
sudo systemctl start docker
sudo systemctl enable docker

1) Create 'docker' group
sudo groupadd docker

2) Add current sudoer user to the group
sudo usermod -aG docker $USER

3) Logout of terminal and login back

4) Restart docker service (Important!)
sudo systemctl restart docker

5) Test docker without sudo
docker image ls
docker container ls