title: Docker container took too many storage of disk
body: <p>I was use <strong>df -hl</strong> for check the status of my vps, but it is seem like,the Storage is took by docker mutil time(i only have 1 wordpress in this vps, there is no have other project)</p>
  
  <p>today i recived a email from linode, they tell me my Storage is finished</p>
  
  <p>Total: 25600 MB
  Used: 25600 MB</p>
  
  <p>i have a wordpress in this vps, which is builded by docker and wordpress</p>
  
  <p>here is the code which from my vps</p>
  
  <pre><code>root@localhost:~# df -hl
  Filesystem      Size  Used Avail Use% Mounted on
  udev            463M     0  463M   0% /dev
  tmpfs            99M  5.9M   93M   6% /run
  /dev/sda         25G  5.0G   19G  22% /
  tmpfs           493M     0  493M   0% /dev/shm
  tmpfs           5.0M     0  5.0M   0% /run/lock
  tmpfs           493M     0  493M   0% /sys/fs/cgroup
  overlay          25G  5.0G   19G  22% /var/lib/docker/overlay2/2ebf8af06fccd1e3a455746e257c990e6d85f848832eaadd636f48d56e6fbefb/merged
  overlay          25G  5.0G   19G  22% /var/lib/docker/overlay2/28044ad06cc4b50d58a331cd644a254c7c90480ad04c1686f2974503da1c98de/merged
  shm              64M     0   64M   0% /var/lib/docker/containers/932928ba7b7ccbbb4dd9f05263fadda8c6764ec7185deefc37c0fc555a2c32d5/mounts/shm
  shm              64M     0   64M   0% /var/lib/docker/containers/67d10956ef387af8327570b7013cc113114a48ccf3654f9ee01041e88e740192/mounts/shm
  overlay          25G  5.0G   19G  22% /var/lib/docker/overlay2/b81fd707a47702b060b462fbb1424bf024c4e593071b0782f4c817ca46a188e2/merged
  shm              64M     0   64M   0% /var/lib/docker/containers/ce2422fff8741ede110a730d1283e0f43792de05a14b2ae9bdb59874fefa5fc2/mounts/shm
  tmpfs            99M     0   99M   0% /run/user/0
  
  </code></pre>
  
  <pre><code>root@localhost:~# docker ps -a
  
  CONTAINER ID        IMAGE                   COMMAND                  CREATED             STATUS              PORTS                            NAMES
  932928ba7b7c        wordpress:latest        "docker-entrypoint.s…"   7 weeks ago         Up 2 weeks          0.0.0.0:1994-&gt;80/tcp             jujuzone_site
  67d10956ef38        phpmyadmin/phpmyadmin   "/run.sh supervisord…"   7 weeks ago         Up 2 weeks          9000/tcp, 0.0.0.0:8081-&gt;80/tcp   phpmyadmin
  ce2422fff874        mysql:5.7               "docker-entrypoint.s…"   7 weeks ago         Up 4 hours          3306/tcp, 33060/tcp              db_jujuzone
  </code></pre>
  
  <pre><code>root@localhost:~# docker system prune
  WARNING! This will remove:
          - all stopped containers
          - all networks not used by at least one container
          - all dangling images
          - all dangling build cache
  Are you sure you want to continue? [y/N] y
  Total reclaimed space: 0B
  </code></pre>