Docker : "permission denied. Are you trying to connect to a TLS-enabled daemon without TLS?"

Docker : “permission denied. Are you trying to connect to a TLS-enabled daemon without TLS?”, when docker pull

solution: add username to group docker, logout and relogin ; make certain the service is running

sudo groupadd docker
sudo gpasswd -a $USER docker (same as sudo usermod -a -G docker $USER)

Logout and re-login. Potentially, you could also exec su -l $USER

sudo cystemctl start docker
sudo cystemctl enable docker #if you want it enabled by default

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