RAID is a data protection technology that combines multiple disks to improve data availability and reliability. It combines multiple physical disks into logical volumes to form an array. As long as there are at least two disks, you can create a RAID array based on the set RAID level. Software RAID is a RAID implementation that does not require physical hardware, also known as "Poor man's RAID".

RAID 0 improves system performance through striping technology. However, the lack of data redundancy greatly increases the risk of single point of failure and reduces system reliability and stability. Once the disk fails, data cannot be recovered, which requires users to bear the risk of data loss. Therefore, although RAID 0 has advantages in improving performance, it is suitable for specific scenarios that require high performance but low data security, and require users to invest more attention and resources in maintenance and data protection.

The main purpose of RAID is to prevent data loss caused by a single point of failure, and to provide data protection through the combination of multiple disks. RAID 0 improves performance by distributing data across multiple disks for striping, but does not provide fault tolerance. If any disk fails, data cannot be recovered. Therefore, RAID 0 is not recommended for storing important data. RAID 0 provides no capacity loss and excellent read/write performance. However, RAID 0 requires at least two disks and the number of disks must be a multiple of 2. Using the mdadm tool to set up dual device RAID0 (striping) in Linux involves the following steps!

Make sure mdadm is installed on your system, as it can be installed directly with the package manager in most linux distributions:

sudo apt-get install mdadm # For Debian/Ubuntu systems

sudo yum install mdadm # For CentOS/RHEL systems

Prepare disk devices. Ensure that there are two disk devices, such as /dev/sda and /dev/sdb. They have been partitioned and formatted. To create a RAID0 array, create a new RAID0 array with mdadm:

sudo mdadm --create --verbose /dev/md0 --level=0 --raid-devices=2 /dev/sda1 /dev/sdb1

/dev/md0 is the new RAID device. --level=0 indicates that the RAID level is 0 (striping). --raid-devices=2 Indicates two devices.

To check the status of the RAID array, run the cat command to view the details:

cat /proc/mdstat

After creating RAID0, you need to format the new device, such as using the ext4 file system:

sudo mkfs.ext4 /dev/md0

Mount RAID devices to a directory such as /mnt/raid0:

sudo mkdir -p /mnt/raid0

sudo mount /dev/md0 /mnt/raid0

Edit the /etc/fstab file and add the following lines to enable automatic mounting on startup:

/dev/md0 /mnt/raid0 ext4 defaults 0 0

Using mdadm to monitor the status of RAID arrays:

sudo mdadm --detail /dev/md0

mdadm can also be used to manage RAID arrays, such as adding or removing disks, checking and repairing arrays, etc. RAID0 does not provide data redundancy, and if one disk fails, the data on the entire array is lost. Therefore, RAID0 is generally not suitable for scenarios where data protection is required. In production environments, it is more common to use configurations such as RAID1, RAID5, or RAID6 that provide a degree of data redundancy.