Docker data path

問題: Docker預設的data path在/vat/lib/docker, 這會隨著container越來越多而佔去許多容量，所以修改路徑。

解決方法: 在/etc/docker底下新增檔案daemon.json寫入

{
  "live-restore": true, #可以stop docker daemon不影響container
  "data-root": "/project/docker",
  "debug": true, #debug log
  "insecure-registries": [],#配置docker的私庫地址
  "registry-mirrors": [
       "https://d8b3zdiw.mirror.aliyuncs.com"
    ],
  "insecure-registries": [
       "https://ower.site.com"
    ]，
}

重啟後生效:
systemctl daemon-reload
systemctl restart docker.service

參考文件: https://docs.docker.com/engine/reference/commandline/dockerd