RAID10

🚀 Safe Migration to RAID 10 with Filesystem Change

This README will guide you through the process of migrating a single hard drive to a RAID 10 configuration, switching from ext4 to XFS, without losing your precious data. 📦🔄

🛠️ Prerequisites

Before starting, make sure you have the following: - Four 16TB hard drives. - Access to a Linux system with mdadm installed. - Complete backup of your data.

📋 Steps to Follow

Step 1: Initial RAID 1 Setup

1. Create a Degraded RAID 1 🏗️

   • Use a new drive and leave space for the original drive to be added later:

    sudo mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/sdb missing
   

   • Note: Replace /dev/sdb with the identifier of the new drive.

2. Format the RAID 1 with XFS 📄

   • Apply the XFS filesystem to the newly created RAID 1:

    sudo mkfs.xfs /dev/md0
   

3. Mount and Copy Data 🔄

   • Mount the RAID and copy data from the original drive:

    sudo mkdir /mnt/md0
    sudo mount /dev/md0 /mnt/md0 
    sudo rsync -avh /mnt/original/ /mnt/md0/
   

Step 2: Add the Original Drive to the RAID 1

1. Format the Original Drive to XFS and Add it to RAID 💾

   • Ensure the original drive is now formatted with XFS and add it to the RAID:

    sudo mdadm --manage /dev/md0 --add /dev/sda1
   

2. Synchronization ⏱️

   • Wait for synchronization to complete by checking the progress:

    watch cat /proc/mdstat
   

Step 3: Expand to RAID 10

1. Convert RAID 1 to RAID 10 📈

   • Add two additional drives and convert the setup to RAID 10:

    sudo mdadm --grow /dev/md0 --level=10 --raid-devices=4 /dev/sdc /dev/sdd
   

2. Finalize RAID 10 Setup 🔧

   • Verify everything is configured correctly:

    sudo mdadm --detail /dev/md0
   

Step 4: Final Filesystem Configuration

1. Adjust XFS Filesystem 🛠️

   • Resize the filesystem to use all available space in RAID 10:

    sudo xfs_growfs /dev/md0
   

2. Mount RAID 10 📁

   • Mount RAID 10 and update fstab for automatic mounts:

    sudo mkdir /mnt/RAID10
    sudo mount /dev/md0 /mnt/RAID10
    echo '/dev/md0 /mnt/RAID10 xfs defaults 0 0' | sudo tee -a /etc/fstab
   

🎉 Conclusion

Congratulations! 🎉 You have successfully configured a RAID 10 and migrated your data without losing a byte. Now you enjoy a more robust and high-performance system. Be sure to verify the integrity of your data and enjoy your new storage setup. 🚀