root@docker_01 ~]# docker images
 REPOSITORY                    TAG                 IMAGE ID            CREATED             SIZE
 hub.c.163.com/public/centos   6.7-tools           b2ab0ed558bb        6 weeks ago         601.9 MB
 hub.c.163.com/public/centos   7.0                 2ce04a284fa8        9 months ago        287.9 MB
 hub.c.163.com/public/centos   latest              997f0ed97903        13 months ago       441.8 MB

[root@docker_01 ~]# docker run --name ceshi -it centos
 Unable to find image 'centos:latest' locally
 Trying to pull repository  docker.io/library/centos   ...

. . . Why is this? I entered by the following method. . .

[root@docker_01 ~]# docker ps -a
 CONTAINER ID        IMAGE                                   COMMAND                  CREATED             STATUS              PORTS               NAMES
 98a498cff145         hub.c.163.com/public/centos:6.7-tools   "/usr/bin/supervisord"   3 minutes ago       Up 3 minutes        22/tcp              ceshi_2
 [root@docker_01 ~]# sh d.sh 98a498cff145
 3396
 [root@98a498cff145 ~]# ls
 anaconda-ks.cfg  d.sh  new.file
 [root@98a498cff145 ~]# exit
 logout
 [root@docker_01 ~]# ls
 anaconda-ks.cfg  d.sh  new.file

[root@docker_01 ~]# cat d.sh
 #!  /bin/bash
 PID=$(docker inspect --format "{{.State.Pid}}" $1)
 echo $PID
 nsenter -t $PID -u -i -n -p

Why are the files in the physical system and the container the same? . . . .