Cannot connect to the Docker daemon at unix:/var/run/docker.sock. Is the docker daemon running?

I have applied every solution available on internet but still I cannot run Docker.

I want to use Scrapy Splash on my server.

Here is history of commands I ran.

docker run -p 8050:8050 scrapinghub/splash
sudo docker run -p 8050:8050 scrapinghub/splash
sudo usermod -aG docker $(whoami)
sudo docker run -p 8050:8050 scrapinghub/splash
newgrp docker
sudo docker run -p 8050:8050 scrapinghub/splash
reboot
sudo docker run -p 8050:8050 scrapinghub/splash
docker run -p 8050:8050 scrapinghub/splash

You can see I tried to restart my server as well, but it didnt help.

see output of ps -aux | grep docker

root@mani:/var/www/html# ps aux | grep docker
root      8524  0.0  0.8 127904 13964 ?        Ssl  17:21   0:00 /usr/bin/dockerd --raw-logs
root      8534  0.0  0.3  90588  5012 ?        Ssl  17:21   0:00 docker-containerd -l unix:///var/run/docker/libcontainerd/docker-containerd.sock --metrics-interval=0 --start-timeout 2m --state-dir /var/run/docker/libcontainerd/containerd --shim docker-containerd-shim --runtime docker-runc
root      8543  0.0  0.0   8812   764 pts/1    S+   17:21   0:00 grep --color=auto docker
root     16356  0.0  0.0  17200   964 pts/1    S    17:14   0:00 newgrp docker
root     20080  0.0  0.0  17200   964 pts/1    S    17:06   0:00 newgrp docker
root     30221  0.0  0.0  17200   964 pts/1    S    17:09   0:00 newgrp docker

You can try out this:

systemctl start docker

It worked fine for me.

P.S.: after if there is commands that you can't do without sudo, try this:

gpasswd -a $USER docker

Just Run

sudo dockerd

dockerd is the daemon service for docker containers, because it is not running in background we're not able to take any actions related to the service, which needs be restarted.

You can get this error if docker doesn't shut down cleanly. The following answer is for the docker snap package.

Run snap logs docker and look for the following:

Error starting daemon: pid file found, ensure docker is not running or delete /var/snap/docker/179/run/docker.pid

Deleting that file and restarting docker worked for me.

rm /var/snap/docker/<your-version-number>/run/docker.pid
snap stop docker
snap start docker

Make sure to replace ‍‍‍‍<your-version-number>‍ with the appropriate version number.

Easy way to fix this issue, try this

sudo su
systemctl start docker
systemctl enable docker
systemctl restart docker