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Network File System (NFS) is a distributed file system protocol. The NFS allows the user to access the files present in the network.

This tutorial will help you to install and configure NFS Server on Ubuntu system and use it on a NFS client system.

Install NFS Server

Before we install the NFS kernal server in our machine we need to update our local repository. For this we can use the following command.

apt-get update

To install and configure the NFS server we are using the following command

apt-get install nfs-kernel-server portmap

Export Share Folder For NFS

We need to create a export directory now, For this we create a directory in the machine and make that folder accessible by the client machines. The folder named share is created in the mnt directory of our machine. 

sudo mkdir /mnt/share

You should remove the restrictive permissions as we want our client machines to access this folder.This can be done by the following command.

chown nobody:nogroup /mnt/share

Now ,to make our clients machines to access the folder we need to create the following configuration in the export file. We can access the exports file and edt by the following command.

vi /etc/exports

We use the following settings as we want to share the share folder created by us.

/etc/exports
/mnt/share     192.168.1.110(rw,sync,no_subtree_check)

Here /mnt/share can only be accessed from IP 192.168.1.110.

To apply the configuration we must run the following command.

exportfs -a

To view the exported directory you can use the following command .

exportfs -v

It will give you the output as follows

Output:
/mnt/share  192.168.1.110(rw,wdelay,no_root_squash,no_subtree_check)

We need to restart the server to make the changes to take place by the following command

systemctl restart nfs-kernel-server

Open Firewall For Clients

After all the configuration we must open the port for the client so that the client can communicate with the server. Here we assume the client ip to be 192.168.102 and we open the port for them 

ufw allow from 192.168.102 to any port nfs

We can check the status of the open ports by following command

ufw status
Output
Status: active

To                         Action      From
--                         ------      ----
OpenSSH                    ALLOW       Anywhere                 
2049                       ALLOW       192.168.1.110        
OpenSSH (v6)               ALLOW       Anywhere (v6)

Mount Share On Client Machine

Next we need to configure the client machine to get the share folder from the client . 

Before instaling NFS client we should update the local repository of your machine. You can use the following command

apt-get update

We need to install the following packages on NFS client system, which is required to mount the remote directory using NFS protocol.

apt-get install nfs-common portmap

Now we should create the mount directories for mounting server nfs exported directories. This can be done by the following command

mkdir /mnt/share

After creating mount directory, mount remote NFS exported directory using following command.

mount 192.168.1.100:/opt/share /mnt/share

We can check the mounted directory by the following command

sudo df -h
Output:
Filesystem                    Size  Used Avail Use% Mounted on
/dev/sda1                      20G  2.8G   16G  16% /
udev                          371M  4.0K  371M  1%  /dev
192.168.1.100:/opt/share       20G  20G    16G  0%  /mnt/share

Test The Connection

We can now create a sample file from the NFS server mount directory and try to access that file from the client mount directory.