10 1U Raspberry Pi 5 Nas Feat 525 Bay Hot Swap

10 1U Raspberry Pi 5 NAS Feat 5.25” Bay Hot Swap: The Ultimate Homelab Storage Solution

1. INTRODUCTION

In the world of homelabs and self-hosted infrastructure, storage challenges consistently rank among top concerns for DevOps engineers and sysadmins. The quest for affordable, space-efficient, and scalable storage solutions often leads to compromises between cost, density, and performance. Enter the Raspberry Pi 5 NAS - a revolutionary approach that combines the accessibility of single-board computers with enterprise-grade storage management concepts.

This guide explores a cutting-edge project from GitHub user wiretap-retro: a 1U rack-mounted NAS solution featuring six 5.25” hot-swap bays powered by Raspberry Pi 5. Designed specifically for homelab enthusiasts and DevOps professionals, this solution addresses three critical infrastructure demands:

1. Space optimization: Full 1U rack compatibility
2. Enterprise features: Hot-swap capability for drive maintenance
3. Cost efficiency: Raspberry Pi 5 base with 3D-printable components

We’ll dissect the technical implementation, analyze performance characteristics, and provide a comprehensive deployment guide. You’ll learn how to transform consumer-grade hardware into a legitimate enterprise-style storage solution suitable for backup targets, media servers, or container storage backends.

Key technical areas covered:

• Storage subsystem architecture
• Network-attached storage (NAS) performance tuning
• Hot-swap hardware implementation
• Software-defined storage management
• RAID configuration tradeoffs
• Thermal management considerations

2. UNDERSTANDING THE 1U RASPBERRY PI 5 NAS

Technical Architecture Overview

The Mini-Rack-1U-Pi-NAS project represents a paradigm shift in affordable storage solutions. At its core lies:

1. Compute Unit: Raspberry Pi 5 (Broadcom BCM2712, Cortex-A76)
2. Storage Interface: 6× 5.25” bays via USB 3.0 to SATA controllers
3. Network Connectivity: Dual Gigabit Ethernet (shared bus)
4. Physical Enclosure: 3D-printed chassis with hot-swap backplane

Why Raspberry Pi 5 for NAS?

The Raspberry Pi 5 introduces several architectural improvements over previous generations:

Feature	Pi 4 B (1GB-8GB)	Pi 5 (4GB-8GB)	NAS Impact
USB Controller	Shared 1x PCIe 2.0	Dedicated 2x PCIe 2.0	2.5× bandwidth
CPU Architecture	Cortex-A72	Cortex-A76	2-3× processing power
Memory Bandwidth	4.4 GB/s	6.4 GB/s	Improved caching
Power Delivery	USB-C 5V/3A	USB-C 5V/5A	Stable drive power

Hot-Swap Mechanics

The 5.25” bay implementation uses a clever mechanical design:

[Front Panel] → [Drive Tray] → [SATA Power/Data] → [Backplane PCB] → [USB 3.0 Host Controller]

Key components:

1. Backplane Circuit: Implements port multiplier functionality
2. Tray Design: Tool-less insertion with secure locking
3. Power Sequencing: Soft power control via GPIO

Performance Considerations

Real-world performance metrics (from Reddit comment testing):

Operation	1× HDD (SMR)	1× SSD	6× HDD RAID 5
Sequential Read	110 MB/s	380 MB/s	280 MB/s
Sequential Write	85 MB/s	350 MB/s	190 MB/s
4K Random Read	0.8 MB/s	28 MB/s	4.2 MB/s
4K Random Write	1.2 MB/s	25 MB/s	3.8 MB/s

Bottleneck analysis:

1. USB 3.0 Contention: 5 Gbps shared across 6 drives
2. Network Limitations: 1 Gbps Ethernet cap (~113 MB/s theoretical)
3. CPU Overhead: Software RAID processing on ARM cores

Comparison to Alternatives

Solution	Cost	Power	Noise	Expandability	Performance
Commercial NAS	\(\)	Low	Low	Limited	High
DIY x86 Server	$$$	High	High	Excellent	Excellent
Pi 5 NAS (This)	$	Low	Medium	Good	Medium

3. PREREQUISITES

Hardware Requirements

Component | Specification | Notes ———-|—————|—— Mainboard | Raspberry Pi 5 8GB | 4GB minimum Storage | 6× 5.25” drives | HDD/SSD compatible Power | ATX PSU (≥300W) | With 6× SATA power Network | Gigabit switch | VLAN capable recommended Rack | Standard 19” | Depth ≥300mm

Critical Hardware Notes:

1. Use USB 3.0 to SATA adapters with UASP support
2. Implement active cooling for Pi 5 (thermal throttling prevention)
3. Quality CAT6/7 cables for network connections

Software Requirements

• Base OS: Raspberry Pi OS Lite (64-bit) Bookworm
• Kernel: 6.1.0-rpi7 or newer
• Essential Packages:

  # Required for storage management
  sudo apt install -y mdadm lvm2 ntfs-3g exfat-fuse smartmontools
  # Network services
  sudo apt install -y samba nfs-kernel-server rsync
  # Monitoring tools
  sudo apt install -y htop iotop iftop lm-sensors
  

Security Pre-Configuration

1. Network Segmentation:
   • Isolate NAS on dedicated VLAN
   • Implement firewall rules limiting access
2. Drive Encryption:

   sudo apt install -y cryptsetup
   sudo cryptsetup luksFormat /dev/sdX1
   

3. User Management:
   • Create dedicated NAS service account
   • Disable root SSH access
   • Implement SSH key authentication

4. INSTALLATION & SETUP

Hardware Assembly

1. 3D Printing Preparation:
   • Use PETG or ABS filament (minimum 0.2mm layer height)
   • Print components from GitHub repository
   • Allow 24-hour curing time for structural integrity
2. Electrical Assembly:

   [Pi 5 USB 3.0 Ports] → [USB Hub] → [6× SATA Adapters]
   [ATX PSU] → [6× SATA Power] + [Pi 5 5V/5A PD]
   

Base OS Configuration

1. Kernel Tuning:

   # /boot/config.txt additions
   # Overclock USB controller
   dtoverlay=rp1-usb
   # Increase USB current
   max_usb_current=1
   

2. Filesystem Optimization:

   # Format drives with 4K alignment
   sudo parted /dev/sdX --align optimal mklabel gpt
   sudo parted /dev/sdX --align optimal mkpart primary 0% 100%
   sudo mkfs.ext4 -b 4096 -E stride=16,stripe-width=64 /dev/sdX1
   

Storage Stack Implementation

1. Software RAID 5 Configuration:

   sudo mdadm --create --verbose /dev/md0 --level=5 --raid-devices=6 \
   /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1
   

2. LVM Configuration:

   sudo pvcreate /dev/md0
   sudo vgcreate nas_vg /dev/md0
   sudo lvcreate -l 100%FREE -n data_lv nas_vg
   

3. Filesystem Creation:

   sudo mkfs.btrfs /dev/nas_vg/data_lv
   

Network Services Setup

1. Samba Configuration (/etc/samba/smb.conf):

   [global]
   server min protocol = SMB3
   server max protocol = SMB3
   socket options = TCP_NODELAY IPTOS_LOWDELAY SO_RCVBUF=131072 SO_SNDBUF=131072
      
   [nas_share]
   path = /mnt/nas_pool
   browseable = yes
   writable = yes
   create mask = 0775
   directory mask = 0775
   

2. NFS Export Setup (/etc/exports):

   /mnt/nas_pool *(rw,async,no_subtree_check,no_root_squash)
   

5. CONFIGURATION & OPTIMIZATION

Storage Performance Tuning

1. Mount Options (/etc/fstab):

   /dev/nas_vg/data_lv /mnt/nas_pool btrfs \
   noatime,compress=zstd:3,space_cache=v2,autodefrag,ssd,discard=async 0 0
   

2. I/O Scheduler:

   # Set deadline scheduler for rotational drives
   echo deadline | sudo tee /sys/block/sdX/queue/scheduler
   

Network Optimization

1. SMB Protocol Tuning:

   # /etc/samba/smb.conf
   use sendfile = yes
   aio read size = 4096
   aio write size = 4096
   

2. TCP Stack Tuning:

   # /etc/sysctl.conf additions
   net.core.rmem_max = 16777216
   net.core.wmem_max = 16777216
   net.ipv4.tcp_rmem = 4096 87380 16777216
   net.ipv4.tcp_wmem = 4096 65536 16777216
   

Security Hardening

1. Access Control:

   # Samba user management
   sudo smbpasswd -a nas_user
   

2. Filesystem Permissions:

   sudo chown -R nas_user:nas_group /mnt/nas_pool
   sudo chmod -R 2770 /mnt/nas_pool
   

6. USAGE & OPERATIONS

Daily Management Tasks

1. Drive Health Monitoring:

   sudo smartctl -a /dev/sdX
   sudo mdadm --detail /dev/md0
   

2. Storage Pool Expansion:

   # Replace failed drive
   sudo mdadm --manage /dev/md0 --remove /dev/sdX1
   sudo mdadm --manage /dev/md0 --add /dev/sdY1
   

Performance Monitoring

1. Real-time Metrics:

   # Combined I/O and network monitoring
   sudo iotop -oPa
   sudo iftop -i eth0
   

2. Long-term Trend Analysis:

   # Install and configure Prometheus Node Exporter
   sudo apt install prometheus-node-exporter
   

7. TROUBLESHOOTING

Common Issues and Solutions

Problem: Slow network transfer speeds
Diagnosis:

iperf3 -c nas_server_ip # Test raw network throughput

Solution:

1. Verify USB link speeds:

   dmesg | grep -i usb
   

2. Check for PCIe/USB contention

Problem: Drive not recognized after hot-swap
Diagnosis:

sudo udevadm monitor --environment

Solution:

1. Verify backplane connections
2. Check kernel messages:

   dmesg | tail -20
   

8. CONCLUSION

This Raspberry Pi 5 NAS implementation demonstrates how enterprise storage concepts can be successfully applied to homelab environments. While not suitable for high-performance production workloads, the solution provides remarkable value considering its ~$300 total cost (excluding drives). The project exemplifies three key DevOps principles:

1. Infrastructure as Code: Reproducible 3D-printable design
2. Software-Defined Storage: Flexible configuration via Linux storage stack
3. Cost Optimization: 90% savings vs commercial solutions

For those looking to expand this setup:

1. Investigate clustered file systems (Ceph, GlusterFS)
2. Implement ZFS with external SAS controllers
3. Add 10GbE networking via PCIe hat

Further Resources:

• Official Raspberry Pi Documentation
• Linux MDADM Guide
• SMB Protocol Optimization

This project represents just the beginning of what’s possible with ARM-based storage solutions. As Raspberry Pi hardware continues evolving, we can expect even more capable homelab storage platforms bridging the gap between consumer and enterprise technology.