docker容器进行文件挂载失败的解决方法

不支持直接挂载文件，会生成与文件同名的目录，导致挂载失败，报错信息如下：

docker: Error response from daemon: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: error during container init: error mounting "/var/prometheus" to rootfs at "/etc/prometheus/prometheus.yml": mount /var/prometheus:/etc/prometheus/prometheus.yml (via /proc/self/fd/6), flags: 0x5000: not a directory: unknown: Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type

解决方法：先在挂载目录下新建文件，然后再创建并运行容器，例如：

              进入挂载目录：cd   /var/prometheus

              新建待挂载文件：touch  prometheus.yml

              创建并运行容器：

docker run --name=prometheus -d -p 9090:9090 --restart=always  -v /var/prometheus/prometheus.yml:/etc/prometheus/prometheus.yml   prom/prometheus