How to mount a directory from hardware node inside OpenVZ container

Sometime it is handy to be able to access a directory from the bare-metal hardware node itself.

One common use of this technique for me is to mount a shared SSD drive which is used by many OpenVZ containers. Since the SSD drive is mounted directly to the bare-metal OS for ie: /mnt/ssd.

Another purpose is to be able to have a common shared directory in the bare-metal server shared between many OpenVZ containers on that server.  The shared directory can even be an NFS Server which means you can have a shared directory between many OpenVZ located in different hardware nodes!  Now that is Cool!

Anyways this is the technique:

1. CREATE THE DESTINATION DIRECTORY

Login to the OpenVZ container where you will be mounting, create the directory and assign all permission. (in this example we will use /mnt/shared_dir as the destination directory path)

mkdir /mnt/shared_dir
chmod 777 /mnt/shared_dir

2. CREATE .mount FILE

Login to shell of your Proxmox hardware node to create <vmid>.mount file.
(in this example you should replace <vmid> with your actual OpenVZ container ID)

(in this example we assume you are trying to share /mnt/ssd from your hardware node)

cd /etc/pve/openvz
nano <vmid>.mount

Type in the following content in your <vmid>.mount file:

#!/bin/bash

. /etc/vz/vz.conf

. ${VE_CONFFILE}

SRC=/mnt/ssd

DST=/mnt/shared_dir

if [ ! -e ${VE_ROOT}${DST} ]; then mkdir -p ${VE_ROOT}${DST}; fi

mount -o noatime -n -t simfs ${SRC} ${VE_ROOT}${DST} -o ${SRC}

3. RESTART THE OPENVZ CONTAINER and TEST

Once you restart your OpenVZ, log into it and issue the following command:

df -h

You should see a new row describing your newly mounted directory.

mount

The mount command can also help you confirm it has been mounted.