Raspberry Pi Network Storage: A DIY Guide

Building a Pi-Based Network Attached Storage (NAS) Solution

Combining a Raspberry Pi with affordable external hard drives provides a straightforward method for creating a remarkably energy-efficient and consistently available network storage solution.

Why Choose a Raspberry Pi NAS?

The appeal of a Pi-based NAS lies in its low power consumption and continuous operation capabilities. Traditional NAS devices can draw significant power, whereas a Raspberry Pi offers a far more economical alternative.

Essential Components

You will need a Raspberry Pi board, along with one or more external hard drives to provide the storage capacity. The drives themselves don't need to be expensive; older or capacity-focused models are perfectly suitable.

Setting Up Your Pi NAS

The following steps will guide you through the process of configuring your own Pi-based NAS. Detailed instructions are available online, covering software installation and configuration.

This setup allows for centralized file storage, accessible from multiple devices on your network. It’s a cost-effective and practical solution for home or small office use.

Benefits of a DIY NAS

• Cost-Effective: Significantly cheaper than pre-built NAS solutions.
• Low Power Consumption: Reduces electricity bills.
• Always-On Availability: Provides constant access to your files.
• Customization: Allows for tailored configurations to meet specific needs.

By leveraging the capabilities of the Raspberry Pi, you can establish a robust and efficient network storage system without a substantial financial investment.

The Advantages of Continuous Network Storage

Maintaining a network storage device that is consistently operational provides exceptional convenience, allowing constant access to your data – or a reliable backup location – from both internal and external network connections.

However, this convenience typically comes with a significant power consumption cost.

Consider, for instance, our office server. It operates continuously and accrues nearly $200 in electricity expenses annually.

In contrast, a network storage solution built around a Raspberry Pi utilizes approximately $5 worth of power each year.

Performance Considerations

While we acknowledge that a dedicated server generally offers greater storage capacity and processing power – capable of tasks like rapidly transcoding large video libraries – this level of performance isn't necessary for all users.

For many individuals, the primary function of a persistently running computer within the home is to function as a file server and a secure repository for data backups.

In these scenarios, the Raspberry Pi provides ample power and represents a substantial reduction in energy costs.

Cost Savings and Efficiency

The core benefit lies in the significant savings achievable through reduced power consumption.

A Raspberry Pi-based solution offers a compelling alternative to traditional servers for basic file serving and backup needs.

This makes it an ideal choice for home users and small offices seeking a cost-effective and energy-efficient network storage solution.

What is Required for Setup?

This guide assumes completion of our prior tutorial, “The HTG Guide to Getting Started with Raspberry Pi.” It is expected that you have already configured your Raspberry Pi, ensuring it is powered on and connected to both a keyboard and a mouse.

Beyond the components detailed in the “Getting Started with Raspberry Pi” tutorial, the following hardware will be necessary:

• A minimum of one USB external hard drive is needed for basic network backups and file sharing.

Alternatively:

• At least two USB external hard drives are recommended for implementing local data redundancy.

That’s all that is needed! A single hard drive will suffice for a straightforward network attached storage solution. However, utilizing at least two hard drives is strongly advised to enable local data redundancy directly on the Raspberry Pi.

For this demonstration, we are employing a matched set of Seagate Backup Plus 1TB Portable External Hard Drives. These drives are compact in size, do not require an external power supply, and were available at a reduced price during our procurement process.

Any external hard drives you currently possess can be utilized, but smaller, low-power drives are preferable. This aligns with the project’s goal of creating a small and energy-efficient NAS that can be discreetly placed and maintained.

Before proceeding, it’s important to understand a couple of key design decisions made during the configuration of our Raspberry Pi NAS. While following these steps precisely is recommended, adjustments may be desired to better suit your specific requirements and network environment.

Firstly, we have chosen to use NTFS-formatted hard disks. This choice allows for easy data transfer should the Raspberry Pi NAS experience a failure or if quick information access is needed via a USB 3.0 connection, bypassing the network.

Secondly, Samba is being used for network shares, primarily due to its compatibility and ease of integration with our predominantly Windows network infrastructure.

Preparing for and Mounting the External Hard Drives

Having assembled the necessary hardware and completed the introductory steps outlined in the Getting Started with Raspberry Pi tutorial (and ensuring Raspian is running), you can now proceed with configuring your Pi as a network attached storage (NAS) device.

Initially, connect the hard drives to the Raspberry Pi, utilizing a USB hub if needed, based on your setup and whether the drives are self-powered or require external power. Once the drives are connected and the Pi is powered on, the configuration process can begin.

For this guide, we are utilizing two hard drives. If you are employing only one drive, simply disregard any commands pertaining to the second drive’s mounting or modification.

All operations will be performed within the terminal. You can either work directly on the Raspberry Pi using LXTerminal in Raspian, or connect remotely via SSH using a tool such as Putty; either method is acceptable.

Upon accessing the command line, the first task is to enable support for NTFS-formatted disks within Raspian. Execute the following command to achieve this:

sudo apt-get install ntfs-3g

Allow a few moments for the packages to download, unpack, and install. Once the NTFS package is installed, identify the unmounted partitions of the connected external hard drives.

sudo fdisk -l

You should observe at least two disks; if a secondary disk is included for data mirroring, as in this example, three disks will be visible:

The first disk,

/dev/mmcb1k0

, represents the SD card within the Raspberry Pi containing the Raspbian installation. This disk should remain untouched.

The second disk,

/dev/sda

, is the first 1TB external hard drive. The third disk,

/dev/sdb

, is the second 1TB external hard disk. The relevant partitions on these disks are

/sda1/

and

/sdb1/

, respectively. Record these hard drive designations.

Before mounting the drives, create directories for their mounting points. For simplicity, directories named USBHDD1 and USBHDD2 will be created for each drive. Enter the following commands at the command line:

sudo mkdir /media/USBHDD1

sudo mkdir /media/USBHDD2

After creating the directories, mount the external drives to their respective locations using these commands:

sudo mount -t auto /dev/sda1 /media/USBHDD1

sudo mount -t auto /dev/sdb1 /media/USBHDD2

The two external hard drives are now mounted to the USBHDD1 and USBHDD2 directories. Create specific directories within both drives to contain shared folders, ensuring organization. Execute these commands:

sudo mkdir /media/USBHDD1/shares

sudo mkdir /media/USBHDD2/shares

Now, install Samba to enable access to the storage from other devices on the network. At the command line, enter:

sudo apt-get install samba samba-common-bin

Confirm the installation by typing Y when prompted. Allow the process to complete. Once Samba is installed, configuration is required. First, create a backup of the Samba configuration file:

sudo cp /etc/samba/smb.conf /etc/samba/smb.conf.old

This creates a backup named smb.conf.old in the same directory as the original.

Edit the Samba configuration file by typing the following at the command line:

sudo nano /etc/samba/smb.conf

This opens the file in the nano text editor. If unfamiliar with nano, consult The Beginner's Guide to Nano, the Linux Command-Line Text Editor.

Use the arrow keys to navigate the file. Note the workgroup identifier, which defaults to WORKGROUP. Modify this if your home network uses a different workgroup name; otherwise, leave it unchanged.

Enable user authentication for Samba storage to prevent unauthorized access. Locate the section reading:

Remove the # symbol from the line security = user to activate username/password verification for Samba shares.

Add a new section to the configuration file by scrolling to the bottom and entering the following text:

[Backup]comment = Backup Folderpath = /media/USBHDD1/sharesvalid users = @usersforce group = userscreate mask = 0660directory mask = 0771read only = no

The text within the brackets defines the folder name as it will appear on the network share; modify this if desired.

Press CTRL+X to exit nano, Y to save changes, and overwrite the file. Restart the Samba daemons at the command prompt:

sudo /etc/init.d/samba restart

Create a user account to access the Pi’s Samba shares. The example uses the username “backups” and password “backups4ever,” but you can choose different credentials. Execute these commands:

sudo useradd backups -m -G users

sudo passwd backups

Enter the password twice to confirm. Then, add “backups” as a Samba user:

sudo smbpasswd -a backups

Enter the password for the backup account when prompted. Restarting the Samba daemon is not necessary, as it is already configured to recognize authenticated users.

Test connectivity to the network share from a Samba-capable machine on the network. From a Windows machine, open Windows Explorer, click Network, confirm the hostname RASPBERRYPI is in the WORKGROUPS workgroup, and click the shared folder Backups:

Enter the credentials created earlier (backups and backups4ever, if following the example). A blank folder indicates successful connection.

To verify functionality, create a simple file from the testing computer. For example:

From the command line, check for the file within the share directory:

cd /media/USBHDD1/shares

ls

The presence of the file confirms successful operation.

Finally, configure the Pi to automatically mount the external hard drives upon restart. Open the fstab file in nano:

sudo nano /etc/fstab

Add the following lines to the file:

/dev/sda1 /media/USBHDD1 auto noatime 0 0

/dev/sda2 /media/USBHDD2 auto noatime 0 0

Press CTRL+X to exit, Y to save, and overwrite the file.

If using only a single hard drive, the configuration is complete. You can now enjoy your low-power NAS.

Establishing Data Redundancy on Your Raspberry Pi NAS

Our Raspberry Pi NAS is now connected to the network, and file transfers are functional. However, a crucial element remains unaddressed. The secondary hard drive is currently configured but remains inactive.

Implementing Automated Data Mirroring

In this part of the guide, we will utilize two robust Linux utilities – rsync and cron – to configure our Raspberry Pi NAS for nightly data mirroring. Specifically, we'll mirror the contents of the /shares/ directory on the primary drive to the /shares/ directory on the secondary drive.

This approach won’t provide real-time RAID-style mirroring, but a daily (or scheduled) data backup to the secondary drive significantly enhances data security.

First, the rsync tool needs to be added to your Rasbian installation. If you are unfamiliar with rsync, we suggest reviewing How to Use rsync to Backup Your Data on Linux for a comprehensive overview of its capabilities.

Execute the following command at the command line:

sudo apt-get install rsync

With rsync installed, we can proceed to create a cron job to automate the file copying process between USBHDD1 and USBHDD2.

At the command line, type:

crontab -e

This command will open your cron scheduling table within the nano text editor, a tool you should now be familiar with from earlier steps in this tutorial.

Navigate to the bottom of the document and add the following line:

0 5 * * * rsync -av --delete /media/USBHDD1/shares /media/USBHDD2/shares/

This instruction directs rsync to compare the two directories every day at 5:00 AM. It copies all data from HDD1 to HDD2 and removes any files in the backup directory that are no longer present on the primary drive. For instance, if a movie file is deleted from HDD1, it will also be removed from the backup during the next synchronization.

Scheduling Considerations

When configuring this command, it’s vital to select a time that doesn’t conflict with other network activity related to your shared folders.

If you utilize your Raspberry Pi NAS as a backup destination for automated software that copies files to the NAS at 5:00 AM, you must either adjust the backup time within that software or modify the cron job’s execution time. Avoid simultaneous data dumping and synchronization to prevent performance issues.

After entering the crontab entry, press CTRL+X to exit and save the file.

To initiate the rsync process immediately and expedite the initial mirroring, execute the same command at the command line:

rsync -av --delete /media/USBHDD1/shares /media/USBHDD2/shares/

That completes the setup! Monitor your Raspberry Pi over the next couple of days to confirm that the scheduled job is running as expected and that data from

/media/USBHDD1/shares/

is being replicated to

/media/USBHDD2/shares/

.

From this point forward, any data added to your Raspberry Pi-powered NAS will be mirrored daily across both hard drives.

Further Exploration

Before concluding, consider these additional How-To Geek articles to enhance your new Raspberry Pi-powered NAS:

• How to Backup Your Gmail Account Using Your Ubuntu PC – Adapt the instructions for Rasbian to transform your Pi NAS into an automated email backup solution.
• What Files Should You Backup On Your Windows PC? – This article provides guidance on identifying essential files for backup to your NAS.
• How To Remotely Backup Your Data for Free with CrashPlan – CrashPlan is a free backup application for Windows, Mac, and Linux, simplifying regular backups to a NAS.

Do you have a Raspberry Pi project idea you’d like us to explore? Share your suggestions, big or small, in the comments below – we enjoy experimenting with the Pi!