Raspberry Pi RAID NAS Server Setup

※ Raspberry Pi RAID NAS Server Setup ※

Hardware:

Raspberry Pi 4 (4GB RAM)
Micro SD card 32GB
2x Integral USB 3.1 flash drives 128GB

OS:

Raspbian Buster

FORMAT DRIVES

Insert drive and list existing partition tables:
```
$ sudo fdisk -l
```

Unmount drive (if needed):

$ sudo unmount /media/pi/<HARD-DRIVE-LABEL>

Partitioning:
```
$ sudo fdisk /dev/sda
```
[m] for help
[o]
[n]
[p]
[1]
[Enter]
[Enter]
[w]
Formatting:
```
$ sudo mkfs.ext4 /dev/sda1
```
[y]

*** DO NOT MOUNT THE DRIVE ***
Repeat steps 1-4 above for other drives.

CREATE RAID ARRAY

Update system and install 'mdadm' RAID package:

$ sudo apt-get update
$ sudo apt-get upgrade
$ sudo apt-get install mdadm

Find out the mount points for each drive:
```
$ blkid
```
-or-
```
$ lsblk
```

Create RAID volume/array:

Linear Mode

$ sudo mdadm --create --verbose /dev/md0 --level=linear --raid-devices=2 /dev/sda1 /dev/sdb1

RAID-0 (Stripe Mode)

$ sudo mdadm --create --verbose /dev/md0 --level=stripe --raid-devices=2 /dev/sda1 /dev/sdb1

-or-

$ sudo mdadm -Cv /dev/md0 -l0 -n2 /dev/sd[ab]1

RAID-1 (Mirror Mode)

$ sudo mdadm --create --verbose /dev/md0 --level=mirror --raid-devices=2 /dev/sda1 /dev/sdb1

-or-

$ sudo mdadm -Cv /dev/md0 -l1 -n2 /dev/sd[ab]1

RAID-4/5/6

$ sudo mdadm --create --verbose /dev/md0 --level=4 --raid-devices=3 /dev/sda1 /dev/sdb1 /dev/sdc1

$ sudo mdadm --create --verbose /dev/md0 --level=5 --raid-devices=3 /dev/sdb1 /dev/sdc1 /dev/sdd1 --spare-devices=1 /dev/sde1

$ sudo mdadm --create --verbose /dev/md0 --level=6 --raid-devices=4 /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

RAID-10

$ sudo mdadm --create --verbose /dev/md0 --level=10 --raid-devices=4 /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1

Confirm RAID array:
```
$ cat /proc/mdstat
```

Save RAID array:

$ sudo -i  
$ mdadm --detail --scan >> /etc/mdadm/mdadm.conf  
$ less /etc/mdadm/mdadm.conf  
$ exit

Create file system:

$ sudo mkfs.ext4 -v -m .1 -b 4096 -E stride=32,stripe-width=64 /dev/md0

NOTE: To change advanced parameters after creation if needed:

$ tune2fs -E stride=n,stripe-width=m /dev/md0

Create mount point and mount file system:
```
$ sudo mkdir /mnt/raidx  
$ sudo mount /dev/md0 /mnt/raidx
```
NOTE: To change the owner of the mount point to pi:
```
$ sudo chown pi:pi /mnt/raidx
```
Check content of the mounted file system:
```
$ ls -la /mnt/raidx
```
Confirm its capacity:
```
$ df -h -x devtmpfs -x tmpfs
```
Update the initial file system (Raspberry Pi uses a RAM disk image when booting up and we want to include our array):
```
$ sudo update-initramfs -u
```
Check UUID of mounted file system:
```
$ blkid
```
-or-
```
$ ls -l /dev/disk/by-uuid
```
Add to fstab (make the drive permanent and auto mount drive at boot):
```
$ sudo nano /etc/fstab
```
Enter new line before the bottom comments and add:
```
UUID=(my_uuid) /mnt/raidx ext4 defaults,noatime 0 0  
```
Save and exit:
[Ctrl+O]
[Ctrl+X]

Retrieve drive parameters and test speeds (optional):

$ sudo hdparm -I /dev/md0
$ sudo hdparm -tT --direct /dev/md0

Reboot:
```
$ sudo reboot
```
Useful commands/Manage Mode:

$ cat /proc/mdstat : show status of all RAID devices
$ mdadm --detail /dev/md0 : detailed information about RAID md0 (mdadm -D)
$ mdadm --detail --brief /dev/md0 : for shorthened/brief details (mdadm -Db)
$ mdadm --query /dev/md0 : quick human-readable summary of RAID md0 (mdadm -Q)
$ mdadm --examine /dev/sdx : information about RAID component device sdx (mdadm -E)
$ mdadm --stop /dev/md0 : stop RAID device md0
$ mdadm --assemble --scan : restart/assemble RAID device

SET UP NAS

Install SAMBA:

$ sudo apt-get install samba samba-common-bin

Set up SAMBA password (for user pi):
```
$ sudo smbpasswd -a pi
```

Edit SAMBA config file:

$ sudo cp /etc/samba/smb.conf /etc/samba/smb.conf.bak  
$ sudo nano /etc/samba/smb.conf

Scroll all the way down to the bottom of the file and add the following code to create NAS file share:

# NAS Share Block  
[NAS]  
path = /mnt/raidx  
comment = RPI4 RAID0 NAS Server  
volume = NAS-Server  
valid users = pi  
read only = NO  
guest ok = NO  
public = NO  
writable = YES  
browsable = YES  
### -rwxr--r--  
create mask = 0744  
### -rwxr-xr-x  
directory mask = 0755  
### All hosts on the 192.168.142 subnet allowed:  
hosts allow = 192.168.142.

Save and exit:
[Ctrl+O]
[Ctrl+X]

Check configuration file for internal correctness:
```
$ testparm
```

Restart SAMBA service:

$ sudo /etc/init.d/samba restart

-or-

$ sudo service smbd restart

Reboot ?
```
$ sudo reboot
```

USAGE ON MAC

Open Finder
Menu "Go" ⟶ "Connect to Server..."

Address: [smb://rpi4/NAS]
[Connect]
Connect As:
- Registered User
Name: pi
Password: ●●●●●●●●
[Connect]

APPENDIX

Commands to check

$ rsync options source destination : remote/local file-copying tool
$ rsync -ahv /mnt/u1/ /mnt/u2/ : example of the above

RAID Levels

Number of Drives /
RAID Level Availability:

2 /
RAID-0 Stripe (Fastest, but no redundancy)
RAID-1 Mirror (Excellent redundancy, good speed)

3 /
RAID-0 Stripe (Fastest, but no redundancy)
RAID-4 Dedicated parity disk (Good speed & redundancy)
RAID-5 Block-level striping with distributed parity (Excellent speed & redundancy)

4 /
RAID-6 Block-level striping with two parity blocks distributed across all member disks (Excellent speed & redundancy)
RAID 10 (nested RAID 1+0) (Excellent speed and redundancy)

References

⇒ mdadm(8) - Linux man page
⇒ How To Manage RAID Arrays with mdadm
⇒ Advantages and disadvantages of various RAID levels
⇒ RAID setup
⇒ A guide to mdadm
⇒ Characteristics of Linux RAID levels
⇒ Build your own Raspberry Pi NAS
⇒ How to Setup a Raspberry Pi Samba Server
⇒ Build a Raspberry Pi RAID NAS Server – Complete DIY Guide
⇒ Partitioning, Formatting, and Mounting a Hard Drive in Linux

gdotdesign/Raspberry Pi RAID NAS Server Setup.md