What is NFS

NFS stands for Network File System. It's a distributed file system that allows user on a client computer to access shared files and directories among networked computers.

Source from: IBM Developer, The NFS architecture

When would use NFS

1. File Sharing in a Network:
   NFS is widely used when you need to share files and directories among multiple computers in a network.
2. Centralized Storage:
   NFS is useful when you want to centralize storage on a dedicated file server.

How to setup NFS on Ubuntu Servers

Pre-required

• 2 instances with ubuntu 22.04 in the same subnet.
• check the 2 instances could connect to each other.

NFS server (one of the instances)

1. create a shared directory and set permission.

$mkdir /shared
$chown nobody.nogroup -R /shared
$chmod 777 -R /shared

2. install NFS package.

$apt update
$apt install nfs-kernel-server -y

3. config the /etc/exports to use a new shared directory and indicate the subnet.

# /etc/exports: the access control list for filesystems which may be exported
#               to NFS clients.  See exports(5).
#
# Example for NFSv2 and NFSv3:
# /srv/homes       hostname1(rw,sync,no_subtree_check) hostname2(ro,sync,no_subtree_check)
#
# Example for NFSv4:
# /srv/nfs4        gss/krb5i(rw,sync,fsid=0,crossmnt,no_subtree_check)
# /srv/nfs4/homes  gss/krb5i(rw,sync,no_subtree_check)
#
/shared 192.168.56.0/24(rw,sync,no_root_squash,no_subtree_check)

4. export the directories specified in the /etc/exports

$exportfs -a

NFS client

1. create a shared directory and set the permission of a directory

$mkdir /shared
$chown nobody.nogroup -R /shared
$chmod 777 -R /shared

2. install NFS package.

$apt update
$apt install nfs-common -y

3. edit the /etc/fstab to mount the shared directory

<master node private ip>:/shared  /shared nfs defaults   0 0

4. mount the shared directory

$mount -a

Testing

1. create a file in /shared on server 1.

$touch /shared/test

2. check the file in /shared on server 2.

$ls /shared/test

Reference

1. Building a SLURM Cluster Using Amazon EC2 (AWS) Virtual Machines