Docker practice 6:cannot Connect to the Docker daemon.

is free to apply to the Aliyun host, of course, to use Docker to deploy my server. But today we have a problem with the following details:

# Docker Info
fata[0000] Cannot connect to the Docker daemon. Is ' docker-d ' running to this host? 
# docker-d
info[0000] +job serveapi (unix:///var/run/docker.sock)   
fata[0000] PID file found, ensure Docker is not Running or Delete/var/run/docker.pid 

First check to see if the Docker daemon is running.

# PS aux | grep Docker
root       691  0.0  1.6 506388 17068?        SSL  Mar07   0:45/usr/bin/docker-d
root      1330  0.0  0.8 124088  ?        Sl   Mar07   0:01 docker-proxy-proto tcp-host-ip 0.0.0.0-host-port 80-container-ip- Container-port
root      9607  0.0  0.0 11720 896 pts/2 s+   16:50   0:00 grep--color=auto Docker

In this way, Docker Deamon is running, but it should not be a mistake to report this error. Then stop it, and then start.

# service Docker Stop
PS aux | grep docker
root      9624  0.0  0.0   11716 636 PTS/2 s+ 16:52   0:00 grep--color=auto Docker
# docker-d
info[0000] +job serveapi (unix:///var/run/docker.sock)   
info[0000] Listening for HTTP on Unix (/var/run/docker.sock) 
INFO[0000] +job init_networkdriver ()                    
info[0000]-job init_networkdriver () = OK (0)           
info[0000] Warning:your Kernel does not support Cgroup swap limit. 
INFO[0000] Loading Containers:start.                   
..........
INFO[0001] Loading containers:done.                    
INFO[0001] Docker daemon:1.5.0 a8a31ef; execdriver:native-0.2; Graphdriver:aufs 
info[0001] +job acceptconnections ()                     
info[0001]-job acceptconnections () = OK (0)      

Well, the most interesting thing is that I worked well under root, but now it's like a hell of a problem. After the completion of the above work, there are still problems. Finally I used sudo to solve the problem. As follows:

# sudo docker info containers:5 images:32 Storage driver:aufs Root Dir:/var/lib/docker/aufs backing Filesystem:extfs dirs:42 Execution driver:native-0.2 Kernel version:3.13.0-32-generic operating System:ubun Tu 14.04.1 LTS