How to Create Software RAID 1 on Oracle Linux

In this comprehensive guide, you’ll learn how to create software RAID 1 on Oracle Linux. RAID 1, also known as mirroring, ensures data redundancy by duplicating data across two or more hard drives. It offers enhanced reliability and fault tolerance in case of drive failure, making it ideal for critical data storage.

Before diving into the process, let’s briefly discuss the differences between software RAID and hardware RAID. Software RAID vs Hardware RAID is a comparison worth considering to understand which option suits your needs best.

Prerequisites

To create a RAID 1 array, you’ll need the following:

Oracle Linux installed on your system.
Two or more hard drives or SSDs of the same size and model for the RAID array.
mdadm package installed on your Oracle Linux system.

How to Create Software RAID 1 on Oracle Linux

Prepare the Hard Drives

Before creating the RAID array, it’s crucial to prepare the hard drives by creating partitions on them. You can use the fdisk command to create partitions. In this example, we’ll use /dev/sdb and /dev/sdc as our drives. Remember to replace these with the correct drive names for your system.

Run fdisk on the first drive:

sudo fdisk /dev/sdb

Press n to create a new partition, followed by p for a primary partition, and 1 for the first partition. Press Enter twice to accept the default start and end sectors.
Change the partition type to Linux RAID auto. Press t, then 1 to select the first partition, and enter fd as the hex code for Linux RAID auto.
Press w to write the changes and exit fdisk.
Repeat steps 1-4 for the second drive (/dev/sdc).

Create the RAID 1 Array on Oracle Linux

With the partitions ready, you can now create the RAID 1 array using the mdadm command.

Run the following command to create the RAID 1 array:

sudo mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/sdb1 /dev/sdc1

Verify the RAID array creation by running:

sudo mdadm --detail /dev/md0

Create a File System

After creating the RAID array, you need to format it with a file system. In this example, we’ll use the ext4 file system.

Format the RAID array:

sudo mkfs.ext4 /dev/md0

Mount the RAID Array on Oracle Linux

To access the RAID array, you’ll need to mount it to a directory. In this example, we’ll use /mnt/raid1.

Create a mount point directory:

sudo mkdir /mnt/raid1

Mount the RAID array:

sudo mount /dev/md0 /mnt/raid1

To ensure the RAID array is mounted automatically at boot, add an entry to the /etc/fstab file:

echo '/dev/md0 /mnt/raid1 ext4 defaults 0 0' | sudo tee -a /etc/fstab

Configure Email Notifications (Optional)

For better monitoring, you can configure mdadm to send email notifications in case of RAID events or failures.

Install the mailx package:

sudo yum install -y mailx

Edit the /etc/mdadm.conf configuration file:

sudo vi /etc/mdadm.conf

Add the following line to configure the email address for notifications (replace [email protected] with your email address):

MAILADDR [email protected]

Save and exit the file.
Update the mdadm configuration:

sudo mdadm --detail --scan | sudo tee -a /etc/mdadm.conf

Conclusion

Congratulations! You’ve successfully set up a software RAID 1 array on Oracle Linux. Your data is now protected by mirroring, providing fault tolerance and redundancy.

To learn more about managing your Oracle Linux system, check out our other guides:

If you have any questions or need further assistance, feel free to leave a comment below.