NFS (Network File System) Setup Using Script

NFS is a distributed file system protocol that allows a user on a client computer to access files over a network as if they were on the local storage. This script automates the setup of an NFS server (master node) and NFS clients (compute nodes) in a distributed computing environment.

NFS Master (Server) Role:

The master is responsible for hosting the shared directories (/storage/data and /storage/scripts) that are accessible to client machines.

Key tasks include:

• Installing the necessary server-side tools (nfs-kernel-server).
• Configuring export rules in /etc/exports to define shared directories and access permissions.
• Restarting and enabling the NFS service to apply changes.

NFS Compute (Client) Role:

The compute node accesses the shared directories hosted on the NFS master.

Key tasks include:

• Installing the client-side tools (nfs-utils).
• Mounting the shared directories to local paths (/storage/data and /storage/scripts).
• Configuring fstab for persistent mounting across reboots.

Security and Permissions:

• Proper access controls are crucial. The script uses no_root_squash for testing and development, but this should be avoided in production.
• Permissions are carefully assigned using chmod 755 instead of 777 to restrict access.

Why Use Scripts for NFS Setup?

Setting up an NFS server and configuring clients involves multiple steps, including installing packages, creating directories, configuring permissions, and making persistent changes. By using a script:

• Consistency: Ensures the same commands are executed correctly every time.

• Efficiency: Reduces manual effort and the risk of human errors.

• Reusability: The scripts can be reused on different nodes or adapted for similar setups.

• Scalability: Simplifies configuration when managing multiple nodes.

  With these scripts, you don’t need to execute commands one at a time; running the script automates the entire process on both the master and slave nodes.

Master Node: NFS Server Setup

This script sets up the master node as the NFS server and shares a directory accessible to specific slave nodes.

• Save the script as setup_nfs_server.sh:

#!/bin/bash

# Variables
EXPORT_DIR="/mnt/nfs_share"
SLAVE_NODES=("192.168.1.101" "192.168.1.102") # Replace with actual slave IPs

# Install required packages
echo "Installing NFS server..."
sudo apt update -y
sudo apt install -y nfs-kernel-server

# Create and configure the shared directory
echo "Setting up shared directory..."
sudo mkdir -p $EXPORT_DIR
sudo chown nobody:nogroup $EXPORT_DIR
sudo chmod 755 $EXPORT_DIR

# Add export rules for the specified slave nodes
echo "Configuring export rules..."
for IP in "${SLAVE_NODES[@]}"; do
    echo "$EXPORT_DIR $IP(rw,sync,no_subtree_check)" | sudo tee -a /etc/exports
done

# Restart and enable NFS server
echo "Restarting NFS server..."
sudo systemctl restart nfs-kernel-server
sudo systemctl enable nfs-kernel-server

# Verify exports
sudo exportfs -v

echo "NFS server setup completed!"

• Run the script:

chmod +x setup_nfs_server.sh

sudo ./setup_nfs_server.sh

Master Node: NFS Server Script Explanation

1. sudo apt update -y

   • Updates the package list to ensure the latest versions of software can be installed.

2. sudo apt install -y nfs-kernel-server

   • Installs the NFS server software required to host shared directories.

3. sudo mkdir -p $EXPORT_DIR

   • Creates the directory to be shared via NFS. The -p option ensures the parent directories are created if they don't exist.

4. sudo chown nobody:nogroup $EXPORT_DIR

   • Sets ownership of the shared directory to a neutral user (nobody) and group (nogroup), ensuring it's accessible to clients.

5. sudo chmod 755 $EXPORT_DIR

   • Sets permissions for the directory to make it readable, writable, and executable by the owner, and readable/executable by others.

6. echo "$EXPORT_DIR $IP(rw,sync,no_subtree_check)" | sudo tee -a /etc/exports

   • Appends export rules to /etc/exports, specifying:

     • rw: Read-write access.
     • sync: Writes to the shared directory are synced immediately.
     • no_subtree_check: Disables subtree checking for performance.

7. sudo systemctl restart nfs-kernel-server

   • Restarts the NFS server to apply changes to the configuration.

8. sudo systemctl enable nfs-kernel-server

   • Ensures the NFS server starts automatically on system reboot.

9. sudo exportfs -v

   • Verifies the export rules and lists the directories shared via NFS.

Slave Nodes: NFS Client Setup

This script configures slave nodes to mount the shared directory from the master node.

• Save the script as setup_nfs_client.sh:

#!/bin/bash

# Variables
NFS_SERVER_IP="192.168.1.100" # Replace with actual server IP
MOUNT_POINT="/mnt/nfs_client"

# Install required packages
echo "Installing NFS client utilities..."
sudo apt update -y
sudo apt install -y nfs-common

# Create a mount point
echo "Creating mount point..."
sudo mkdir -p $MOUNT_POINT

# Mount the shared directory
echo "Mounting NFS shared directory..."
sudo mount $NFS_SERVER_IP:/mnt/nfs_share $MOUNT_POINT

# Persist the mount in /etc/fstab
echo "Configuring persistent mount..."
echo "$NFS_SERVER_IP:/mnt/nfs_share $MOUNT_POINT nfs defaults 0 0" | sudo tee -a /etc/fstab

# Verify the mounted directory
df -h $MOUNT_POINT

echo "NFS client setup completed!"

• Run the script:

chmod +x setup_nfs_client.sh
sudo ./setup_nfs_client.sh

Slave Node: NFS Client Script Explanation

1, sudo apt update -y - Updates the package list to ensure the latest software versions are installed.

2. sudo apt install -y nfs-common

   • Installs the necessary NFS utilities for the client system to connect to the NFS server.

3. sudo mkdir -p $MOUNT_POINT

   • Creates a local directory to mount the shared directory from the server.

4. sudo mount $NFS_SERVER_IP:/mnt/nfs_share $MOUNT_POINT

   • Mounts the shared directory from the server (/mnt/nfs_share) to the local mount point ($MOUNT_POINT).

5. echo "$NFS_SERVER_IP:/mnt/nfs_share $MOUNT_POINT nfs defaults 0 0" | sudo tee -a /etc/fstab

   • Adds an entry to /etc/fstab to ensure the shared directory is automatically mounted at boot.

6. df -h $MOUNT_POINT

   • Displays the disk usage and verifies the shared directory is successfully mounted.

Verification Steps

• On the Master Node:
  1. Check NFS Service:

sudo systemctl status nfs-kernel-server

2. List Exported Directories:

sudo exportfs -v

3. Firewall Configuration:

Ensure ports 2049, 111, and 20048 are open.

On the Slave Nodes:

1. Verify Mount:

df -h /mnt/nfs_mount

2. Test File Creation:

touch /mnt/nfs_mount/suraj.txt
ls -l /mnt/nfs_mount

3. Check Active Mounts:

mount | grep nfs

Advantages of NFS

• Centralized Data Management: Simplifies data sharing by allowing multiple clients to access files stored on the server.

• Flexibility: Clients can dynamically mount shared directories and work as if they were local directories.

• Scalability: Suitable for setups with multiple clients requiring access to shared resources.

• Cross-Platform Support: Works across different operating systems.

Additional Notes

• Replace placeholder IPs and paths with yours VMs machine.
• Ensure persistent mounts are configured in /etc/fstab.
• Use the scripts for easier replication across systems.
• For troubleshooting, check logs using:

sudo journalctl -xe | grep nfs

This implementation combines automation and consistency, making NFS setup seamless for both the master and slave nodes.

------------------Screnshots--------------------

1. server script

2. Client Script

3. Verify Ip and mnt

4. Final Output

👨‍💻 𝓒𝓻𝓪𝓯𝓽𝓮𝓭 𝓫𝔂: Suraj Kumar Choudhary | 📩 𝓕𝓮𝓮𝓵 𝓯𝓻𝓮𝓮 𝓽𝓸 𝓓𝓜 𝓯𝓸𝓻 𝓪𝓷𝔂 𝓱𝓮𝓵𝓹: csuraj982@gmail.com