Implementing RAID configurations for deployed NAS systems

Story

March 17, 2025

Steven Petric

Curtiss-Wright

Implementing RAID configurations for deployed NAS systems

Network-attached storage (NAS) systems for mission-critical applications often rely on a redundant array of independent disk (RAID) configurations to mitigate data loss from disk failures, improve data throughput speed, and maximize storage efficiency. Users can effectively implement RAID to optimize their NAS systems and ensure critical data protection in deployed environments by carefully considering storage capacity, performance, and platform requirements.

By combining multiple physical disks into a single system, RAID distributes data using various methods to achieve redundancy and speed. There are five primary RAID architectures – RAID 0, 1, 5, 6, and 10 (configurations 2, 3, and 4 are essentially obsolete) – each of which offers unique advantages and drawbacks.

RAID 0 is designed for speed and employs striping to distribute data across multiple disks: Striping entails dividing the data into blocks and spreading the blocks across multiple disks. RAID 0 can be formed using two or more disks of various types, such as FC, SATA, NVMe, SSD, or HDD. RAID 0 carries the advantage of maximizing storage efficiency by fully utilizing all disks in the array, contributing to total available capacity, making it a cost-efficient option for using all the disk capacity. RAID 1 is known as disk mirroring because it stores identical copies of data stored on multiple disks. Primary drawbacks of RAID 1 are slower speed, reduced capacity, and increased cost. As data is replicated across multiple disks, the usable storage capacity is halved when compared to RAID 0, but RAID 1 does carry the advantage of being able to recover from one failed disk.

RAID 5 leverages striping and distributed parity to provide data redundancy and enhanced performance, with a minimum of three disks required to build a RAID 5 array. Data is segmented into smaller blocks and uniformly distributed across all disks through block-level striping. Unlike RAID 1, where a complete duplicate of data is stored on each disk, RAID 5 distributes the parity information across all disks, thereby making it more resilient from failures. The advantages of RAID 5 include data recovery from one failed disk and greater capacity and cost efficiency than RAID 1 for larger arrays with more than three disks. The disadvantages: reduced capacity, increased cost, rebuild required after failure, and initial high build time.

RAID 6 employs block-level striping with double-distributed parity, so it can withstand the failure of up to two disks without compromising data integrity. A minimum of four disks is required to build a RAID 6 array. Similar to RAID 5, RAID 6 utilizes block-level striping to distribute data across drives. The advantages of RAID 6 include excellent data recovery from up to two failed disks and greater capacity and cost than RAID 1 for larger arrays (>4 disks). The disadvantages of RAID 6 are reduced capacity, increased cost, rebuild required after failure, and extended initial build time.

RAID 10, also known as RAID 1+0, also uses the striping of RAID 0 and mirroring of RAID 1. It requires a minimum of four disks and offers a combination of performance and data redundancy. Essentially, a RAID 0 controller stripes data onto two RAID 1 arrays. In comparison to RAID 5 or RAID 6, RAID 10 delivers superior speed due to the RAID 0 striping. However, RAID 10 consistently entails a 50% reduction in capacity and increased cost compared to RAID 0, because half the storage capacity is used for data redundancy. Whereas RAID 1 protects data in the event of disk failure, RAID 10 tolerates the failure of one disk anywhere in the array.

The advantages of RAID 10 are recovery from one failed disk and speed, but that 50% reduction in capacity is a disadvantage, as is the doubled cost compared to RAID 0.

NAS devices are almost exclusively equipped with SSDs [solid-state drives], using SATA or NVMe interface standards. Deployed vehicles often operate in hostile environments, exposing stored DAR [data at rest] to internal and external threats from nation-states, hackers, and bad actors. Because the deployed vehicles frequently carry highly sensitive, up to Top Secret-level data – including maps, plans, and sensor information – stringent physical-security protocols and robust encryption methods must be implemented to safeguard the critical data from unauthorized access, exploitation, or loss.

Encryption protects data from unauthorized access but can’t prevent data loss from disk failure; implementing RAID on the NAS mitigates this risk and ensures data integrity. RAID 1, 5, 6, or 10 configurations are recommended for deployed NAS systems to prevent data loss from disk failure. (Figure 1.)

[Figure 1 ǀ The HSR10 (High-Speed Recorder 10) with CSfC encryption is a COTS [commercial off-the-shelf] high-speed network recorder and NAS device that supports RAID 0, 1, 5, 6, 10.]

Steve Petric is senior product manager, Curtiss-Wright Defense Solutions.

Curtiss-Wright Defense Solutions https://www.curtisswrightds.com/