install

# Parent direct for NFS shares and subdirectories
/exports
cd /exports
mkdir backup
mkdir documents

# Now install Packages
sudo apt install nfs-kernel-server
systemctl status nfs-kernel-server

# Create a fresh one exports configuration  
cat /etc/exports
mv /etc/exports /etc/exports.orig
nano /etc/exports
#Put this in the exports file for nfs Server
/exports/backup IP_SERVER_CLIENTS/Subnet_IP (rw,no_subtree_check)
/exports/documents IP_SERVER_CLIENTS/Subnet_IP (rw,no_subtree_check)
# Restar the services 
systemctl restart nfs-kernel-server
# Test Files and server service
cd /exports 
nano /backup/text1.txt 
nano /documents/text2.txt

# Connect other Client server

apt install nfs-common
showmount
# Get IP of IP_OF_SERVER_NFS
ip addr show
# Back to client 
showmount  --exports IP_OF_SERVER_NFS 

# Create Share directories in Client
mkdir /mnt/nfs
mkdir /mnt/nfs/backup
mkdir /mnt/nfs/documents

# Mount client NFS EXPORT
sudo mount IP_OF_SERVER_NFS:/exports/backup /mnt/nfs/backup
sudo mount IP_OF_SERVER_NFS:/exports/documents /mnt/nfs/documents
cat /mnt/nfs/backup/text1.txt

# Umount client NFS EXPORT
sudo umount /mnt/nfs/backup
sudo umount /mnt/nfs/backup

# Mount NFS in on demand Works better and only with autofs
# Unmount directories and Remove Directories that not have any thing mounted with are mounnted first unmount
sudo rm -r backup documents

# Install autofs
apt install autofs
systemctl status autofs

# Configure
nano /etc/auto.master
# Use this configuration bellow in the final of file ( --ghost make sure the files exist in mount location)
/mnt/nfs/ /etc/auto.nfs --ghost --timeout=60 

# Edit next file this is Configuration (rw = read and Writte) serverIP:/loaction_of_server
nano /etc/auto.nfs
backup -fstype=nfs4, rw IP_OF_SERVER_NFS:/exports/backup
documents -fstype=nfs4, rw IP_OF_SERVER_NFS:/exports/documents

# This is First files read by nfs Auto 
tail -n 1 /etc/auto.master ( here give where read and conf of consistance)
cat /etc/auto.nfs  ( This file configuration where will be mounted) 
systemct restart autonfs 
ls -l /mnt/nfs/documents ( If liest sub_directories just that will be mounted)
df -h 
ls -l /mnt/nfs   ( just list base directories and atomaticly mount the server) after 60 seconds 
df -h 
# Verify what happen
watch "mount | grep nfs"


# Video https://www.youtube.com/watch?v=zmDIfJtCKCk