一、首先查看容器配置

docker inspect 容器id

#查到MergedDir

  "MergedDir": "/var/lib/docker/overlay2/2897c18dd38a69768f9ccb913d57a8d2a19eed347bcf6d05dc3cc85153ac566e/merged",
  "UpperDir": "/var/lib/docker/overlay2/2897c18dd38a69768f9ccb913d57a8d2a19eed347bcf6d05dc3cc85153ac566e/diff",
  "WorkDir": "/var/lib/docker/overlay2/2897c18dd38a69768f9ccb913d57a8d2a19eed347bcf6d05dc3cc85153ac566e/work",

二、切换目录

#切换至目录merged
cd /var/lib/docker/overlay2/2897c18dd38a69768f9ccb913d57a8d2a19eed347bcf6d05dc3cc85153ac566e/merged

#接下去就是容器的根/目录了