Basic Docker container reports runlevel unknown
问题 When I run a basic Docker container (from within Google Cloud Shell) like so docker pull debian docker run -i -t debian:wheezy /bin/bash and then type runlevel at the running container's shell prompt, the run level is unknown . Am I supposed to install ( apt-get ) particular packages in order to add support for run levels. If so, which ones, or what else could be wrong? 回答1: Docker is an application isolation tool, not an OS virtualization tool. Runlevels are at the OS level, the OS comes up,