What are NAS, SAN, iSCSI, and NFS? Differences, Setup, and Configuration in Ubuntu and Windows.

DevOpsbyAshish February 19, 2025

 In enterprise environments, storage solutions like NAS (Network-Attached Storage) and SAN (Storage Area Network) play crucial roles in managing data efficiently. Additionally, iSCSI and NFS are protocols used for accessing and managing storage. Let’s dive into the details.

1️⃣ What is NAS (Network-Attached Storage)? 🖥️

NAS is a storage device that connects to a network and provides file-based access to multiple clients. It is like a file server but optimized for storage and file sharing.

✅ Key Features:

  • Uses standard Ethernet (LAN) connections.
  • Provides file-level access using protocols like NFS, SMB (Windows), FTP, or AFP (Mac).
  • Easy to set up and manage.
  • Suitable for home networks, small businesses, and backup solutions.

🎯 Use Cases:

  • File sharing among users.
  • Media storage for streaming.
  • Backup and archival solutions.

2️⃣ What is SAN (Storage Area Network)? 🏢

SAN is a high-speed storage network that provides block-level storage to servers. Unlike NAS, which operates at the file level, SAN operates at the block level, making it ideal for databases and high-performance applications.

✅ Key Features:

  • Uses Fiber Channel (FC) or iSCSI over Ethernet.
  • Provides block-level access, meaning data is accessed as if it were a local disk.
  • Requires dedicated SAN switches and storage arrays.
  • Best for large enterprises, virtualization (VMware, Hyper-V), and high-performance databases.

🎯 Use Cases:

  • Large databases (Oracle, MySQL, SQL Server).
  • Virtualization environments (VMware, Hyper-V).
  • High-performance applications requiring low latency.

3️⃣ What is iSCSI (Internet Small Computer Systems Interface)? 🔌

iSCSI is a protocol that allows SAN storage to be accessed over Ethernet. It allows block-level storage to be transmitted over TCP/IP networks.

✅ Key Features:

  • Uses standard Ethernet (LAN/WAN) instead of expensive Fiber Channel.
  • Provides block-level access, making it behave like a local disk.
  • Ideal for VMware, Hyper-V, and enterprise applications.

🎯 Use Cases:

  • Virtual machines and databases that need dedicated storage.
  • Expanding storage over existing Ethernet networks without investing in Fiber Channel.

4️⃣ What is NFS (Network File System)? 📂

NFS is a file-sharing protocol used in Unix/Linux environments. It allows multiple clients to mount remote file systems over a network.

✅ Key Features:

  • Used mainly in Linux and Unix environments.
  • Provides file-level access (like NAS).
  • Can be mounted as a local drive on client machines.
  • Supported in VMware ESXi for shared storage.

🎯 Use Cases:

  • Shared storage in Linux servers.
  • Home directories in enterprise environments.
  • Storage for VMware datastores.
How to Set Up NAS, SAN, iSCSI, and NFS in VMware ESXi and Ubuntu

📌 Step 1: Set Up NAS (NFS) in Ubuntu

(Network-Attached Storage - File-Based Storage for VMware ESXi)

1️⃣ Install and Configure NFS on Ubuntu

  1. Update the system and install the NFS server:
    sudo apt update && sudo apt install nfs-kernel-server -y
  2. Create a shared directory for NFS storage:
    sudo mkdir -p /srv/nfs/share
    sudo chown nobody:nogroup /srv/nfs/share
    sudo chmod 777 /srv/nfs/share
  3. Edit the NFS exports file:

    sudo nano /etc/exports
    Add the following line to share the folder with ESXi:
    /srv/nfs/share 192.168.1.0/24(rw,sync,no_subtree_check)
  4. Apply the changes and restart the NFS service:
    sudo exportfs -a
    sudo systemctl restart nfs-kernel-server

2️⃣ Add NFS Storage in VMware ESXi

  1. Log in to the vSphere Client.
  2. Click on ESXi Host → Storage → New Datastore.
  3. Select Mount NFS Datastore and click Next.
  4. Enter the following details:
    • NFS Server: Ubuntu Server IP
    • Folder Path: /srv/nfs/share
    • Datastore Name: NFS_Datastore
  5. Click Next → Finish.

🎯 NFS is now available as shared storage for VMware ESXi!

📌 Step 2: Set Up SAN (iSCSI) in Ubuntu

(Storage Area Network - Block-Level Storage for VMware ESXi)

1️⃣ Install and Configure iSCSI Target on Ubuntu

  1. Install the iSCSI target service:

    sudo apt update && sudo apt install tgt -y
  2. Create a virtual disk for iSCSI storage:

    sudo fallocate -l 20G /srv/iscsi_disk.img
    sudo chmod 600 /srv/iscsi_disk.img
  3. Configure the iSCSI Target:

    sudo nano /etc/tgt/conf.d/iscsi.conf
    Add the following configuration:

    <target iqn.2025-02.local.ubuntu:storage>
        backing-store /srv/iscsi_disk.img
        initiator-address 192.168.1.0/24
    </target>
  4. Restart the iSCSI target service:
    sudo systemctl restart tgt
    sudo systemctl enable tgt

2️⃣ Add iSCSI Storage in VMware ESXi

  1. Log in to the vSphere Client.
  2. Click on ESXi Host → Storage Adapters.
  3. Click Add Storage Adapter → Select Software iSCSI Adapter.
  4. Select the iSCSI Adapter → Click Configure iSCSI.
  5. Under Dynamic Discovery, click Add and enter the iSCSI Target IP (Ubuntu Server).
  6. Click Rescan Storage Adapters.
  7. Go to Storage → New Datastore.
  8. Select VMFS → Choose the discovered iSCSI LUN → Format and Finish.

🎯 iSCSI SAN is now available as block storage for VMware ESXi!

📌 Step 3: Set Up iSCSI Initiator on Windows (Optional)

(If you want Windows machines to connect to iSCSI storage instead of ESXi)

  1. Open iSCSI Initiator (Start → Search iSCSI Initiator).
  2. Under Discovery, click Discover Portal and enter the Ubuntu iSCSI Target IP.
  3. Go to Targets, select the discovered target, and click Connect.
  4. Open Disk Management (diskmgmt.msc), initialize, and format the new iSCSI disk.

🎯 Windows can now use iSCSI storage as a local disk!


🖥️🔧Setting Up NAS, SAN, iSCSI, and NFS in Windows 
Windows provides built-in tools to configure and manage NAS, SAN, iSCSI, and NFS storage solutions. Let’s go through step-by-step setup for each.

📌 1. Setting Up NAS (Network-Attached Storage) in Windows

NAS in Windows can be set up using SMB (Server Message Block) file sharing.

🚀 Steps to Create a NAS File Share in Windows

Step 1: Create a Shared Folder

1️⃣ Right-click on a folder you want to share.
2️⃣ Click Properties → Sharing → Advanced Sharing.
3️⃣ Check "Share this folder" and click Permissions.
4️⃣ Set Everyone to Full Control (or limit as needed).
5️⃣ Click OK → Apply.

Step 2: Access the Shared Folder

On another Windows machine:
1️⃣ Open File Explorer and enter \\<NAS_SERVER_IP>\<Share_Name> in the address bar.
2️⃣ Authenticate if needed, and the folder will be accessible.

🎯 Use Cases:
✅ Office file sharing.
✅ Centralized storage for a team.
✅ Media streaming (videos, music).

📌 2. Setting Up a SAN (iSCSI) in Windows

Windows Server includes iSCSI Target Server, allowing it to act as a SAN storage provider.

🚀 Steps to Configure iSCSI Target Server (SAN)

Step 1: Install iSCSI Target Server (Windows Server)

1️⃣ Open Server Manager → Click Manage → Add Roles and Features.
2️⃣ Select Role-based or feature-based installation → Click Next.
3️⃣ Under File and Storage Services, select iSCSI Target Server and install.

Step 2: Configure an iSCSI Target

1️⃣ Open Server Manager → File and Storage Services → iSCSI.
2️⃣ Click New iSCSI Virtual Disk and select a volume to store the disk.
3️⃣ Name the disk and specify size (Fixed = Thick, Dynamically Expanding = Thin).
4️⃣ Create a new iSCSI Target → Add the initiator’s IP/Hostname.
5️⃣ Configure CHAP authentication if required.
6️⃣ Click Create to finalize.

Step 3: Connect iSCSI Initiator (Windows Client)

1️⃣ On the client machine, open iSCSI Initiator (iscsi initiator in Start).
2️⃣ Under Discovery → Add Portal → Enter iSCSI Target IP.
3️⃣ Under Targets, select the discovered target and click Connect.
4️⃣ Open Disk Management (diskmgmt.msc), initialize, and format the new disk.

🎯 Use Cases:
✅ High-performance database storage.
✅ Expanding storage for virtual machines (Hyper-V).
✅ Centralized block storage.

📌 3. Setting Up iSCSI Initiator (Client) in Windows

To connect to an iSCSI SAN from a Windows client:

1️⃣ Open iSCSI Initiator (Start → Search iSCSI Initiator).
2️⃣ Under Discovery, click Discover Portal.
3️⃣ Enter the IP address of the iSCSI Target Server.
4️⃣ Click Targets, select the discovered target, and Connect.
5️⃣ Open Disk Management (diskmgmt.msc), initialize, and format the new disk.

🎯 Use Cases:
✅ Connecting Windows machines to a SAN.
✅ Using a remote iSCSI disk as local storage.

📌 4. Setting Up NFS Server in Windows

Windows Server includes NFS Server, allowing it to share files with Linux systems.

🚀 Steps to Set Up NFS Server in Windows Server

Step 1: Install NFS Server Role

1️⃣ Open Server Manager → Click Manage → Add Roles and Features.
2️⃣ Select Role-based or feature-based installation → Click Next.
3️⃣ Under File and Storage Services, select Server for NFS and install.

Step 2: Create an NFS Share

1️⃣ Right-click on a folder → Properties → NFS Sharing.
2️⃣ Click Manage NFS Sharing → Check "Share this folder".
3️⃣ Click Permissions, select All Machines, set access to Read-Write.
4️⃣ Click Apply → OK.

Step 3: Mount the NFS Share (Linux Client)

On a Linux machine:

sudo mount -t nfs <Windows_Server_IP>:/share /mnt

🎯 Use Cases:
✅ Sharing files between Windows and Linux.
✅ Providing storage for Linux-based applications.
✅ VMware ESXi datastores.

🛠️ Difference Between NAS, SAN, iSCSI, and NFS

FeatureNAS 🖥️SAN 🏢iSCSI 🔌NFS 📂
TypeFile StorageBlock StorageBlock StorageFile Storage
ProtocolNFS, SMB, AFPFiber Channel, iSCSIiSCSI over TCP/IPNFS
PerformanceMediumHighHighMedium
AccessFile-levelBlock-levelBlock-levelFile-level
Best ForFile sharing, backupsDatabases, VirtualizationVirtualization, SANLinux file sharing, VMware
DevOpsbyAshish

Posted by DevOpsbyAshish