在WSL(Windows Subsystem for Linux，适用于Linux的Windows子系统)下通过systemctl命令启动某些服务将造成System has not been booted with systemd as init system (PID 1). Can’t operate.这样的错误；
以启动docker 为例：
sudo systemctl restart docker错误信息如下：
System has not been booted with systemd as init system (PID 1). Can't operate.Failed to connect to bus: Host is down- 解决方案
尝试使用以下方法启动服务：
sudo service docker start
