Objective

The objective is to configure basic client/server NFS configuration on Debian 9 Stretch Linux

Operating System and Software Versions

  • Operating System: - Debian 9 Stretch

Requirements

Privileged access to your Debian Linux installation.

Difficulty

EASY

Conventions

  • # - requires given command to be executed with root privileges either directly as a root user or by use of sudo command
  • $ - given command to be executed as a regular non-privileged user

NFS Server Setup

NFS Server Installation

The first step is to install NFS server binaries. To do that use apt command to install nfs-kernel-server package:
# apt-get install nfs-kernel-server
Confirm that NFS server is up and runing:
# systemctl status nfs-kernel-server
‚óŹ nfs-server.service - NFS server and services
   Loaded: loaded (/lib/systemd/system/nfs-server.service; enabled; vendor preset: enabled)
   Active: active (exited) since Mon 2017-06-05 14:20:17 AEST; 1min 8s ago
 Main PID: 1752 (code=exited, status=0/SUCCESS)

linuxconfig systemd[1]: Starting NFS server and services...
linuxconfig systemd[1]: Started NFS server and services.

Export NFS directory

Next, we need to export NFS directory. This directory will be eventual mounted remotely, hence accessible via NFS client host. For the purpose of this tutorial we create and export directory called /var/nfs-export. First, create a new nfs-export directory:
# mkdir /var/nfs-export
For testing purposes also create an arbitrary text file:
# cd /var/nfs-export/
# echo LinuxConfig.org > file.txt
# cat file.txt 
LinuxConfig.org
Once ready, used your favorite text editor and create a new NFS export entry within /etc/exports configuration file. For example :
/var/nfs-export *(rw,sync,no_subtree_check,no_root_squash)
The above export will export /var/nfs-export directory to any host with any IP address with read-write access. This is a highly unsecure export. For more NFS export examples enter $ man exports.

To apply changes within /etc/exports configuration file, reload all NFS exports with:
# exportfs -a
If you wish to start your NFS server after reboot, you need enable it with systemctl systemd command:
# systemctl enable nfs-kernel-server
Synchronizing state of nfs-kernel-server.service with SysV service script with /lib/systemd/systemd-sysv-install.
Executing: /lib/systemd/systemd-sysv-install enable nfs-kernel-server

NFS Client

Now that the NFS export directory is available to a remote mount. Let's install NFS client on our client system:
# apt-get install nfs-common
Create a new directory which will be used as a NFS mount point to remotely mount previously exported /var/nfs-export directory:
# mkdir /mnt/nfs
Mount remote NFS export directory:
# mount -t nfs YOUR-NFS-SERVER-IP:/var/nfs-export /mnt/nfs/
Check the content of the NFS export directory and test write access by creating a new empty test file:
# cat /mnt/nfs/file.txt 
LinuxConfig.org
# touch /mnt/nfs/test
# ls /mnt/nfs/
file.txt  test
To permanently mount NFS export directory on your NFS client, insert a following line into your /etc/fstab config file:
YOUR-NFS-SERVER-IP:/var/nfs-export /mnt/nfs/    nfs
At the moment regular users do not have a write access to the /mnt/nfs/. Any write attempt to this directory will be denied with the following error message:
$ touch /mnt/nfs/file
touch: cannot touch 'file': Permission denied
While there are multiple and more secure solutions to this issue, the fastest solution could be to give a write access to the /mnt/nfs/ on the client host to a specific user who needs a write access or to give it to everybody. Example:
# chmod o+w /mnt/nfs/