ubuntu docker命令免sudo 执行

小白安装docker的时候遇到的一个炒鸡大坑

docker: Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock: Post http://%2Fvar%2Frun%2Fdocker.sock/v1.40/containers/create: dial unix /var/run/docker.sock: connect: permission denied.

电脑配置

                          ./+o+-       用户名@主机名
                  yyyyy- -yyyyyy+      OS: Ubuntu 18.04 bionic
               ://+//////-yyyyyyo      Kernel: x86_64 Linux 4.15.0-72-generic
           .++ .:/++++++/-.+sss/`      Uptime: 6m
         .:++o:  /++++++++/:--:/-      Packages: 4914
        o:+o+:++.`..```.-/oo+++++/     Shell: zsh 5.4.2
       .:+o:+o/.          `+sssoo+/    Resolution: 1280x1024
  .++/+:+oo+o:`             /sssooo.   DE: XFCE
 /+++//+:`oo+o               /::--:.   WM: Xfwm4
 \+/+o+++`o++o               ++////.   WM Theme: Mojave-light
  .++.o+++oo+:`             /dddhhh.   GTK Theme: TraditionalOk [GTK2]
       .+.o+oo:.          `oddhhhh+    Icon Theme: Tela
        \+.++o+o``-````.:ohdhhhhh+     Font: Sans 10
         `:o+++ `ohhhhhhhhyo++os:      CPU: Intel Core i5-6500 @ 4x 3.6GHz [53.0°C]
           .o:`.syhhhhhhh/.oo++o`      GPU: Mesa DRI Intel(R) HD Graphics 530 (Skylake GT2) 
               /osyyyyyyo++ooo+++/     RAM: 714MiB / 15920MiB
                   ````` +oo+++o\:    
                          `oo++.      

问题：

╰─$ docker run hello-world
docker: Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock: Post http://%2Fvar%2Frun%2Fdocker.sock/v1.40/containers/create: dial unix /var/run/docker.sock: connect: permission denied.
See 'docker run --help'.

解决办法：
临时对策，未找到永久对策。
How to fix docker: Got permission denied while trying to connect to the Docker daemon socket
打不开连接看下面：

    ubuntu@ip-172-31-21-106:/var/run$ ls -lrth docker.sock
    srw-rw---- 1 root root 0 Oct 17 11:08 docker.sock
    ubuntu@ip-172-31-21-106:/var/run$ sudo chmod 666 /var/run/docker.sock
    ubuntu@ip-172-31-21-106:/var/run$ ls -lrth docker.sock
    srw-rw-rw- 1 root root 0 Oct 17 11:08 docker.sock

把/var/run/docker.sock文件的权限改为666
有的系统路径在/run/docker.sock

参考

ubuntu docker命令免sudo 执行
Ubuntu下docker使用非root权限运行docker
史上最全Docker环境安装指南