1. Reasons

The docker process uses UNIX sockets instead of TCP ports. By default, UNIX socket belongs to root user, so it needs to   Root privileges   To access

2. Solutions

# Create a docker group
sudo groupadd docker
# Check if the current user is in the docker group          
sudo gpasswd -a $your_user_name docker   
# Add the current user to the docker group
sudo gpasswd -a $USER docker
# Update group information  
newgrp docker

3. Inspection results

docker version