NAS vs. SAN vs. DAS: Which Is Right for You?

What features do I need in business storage?

Navigating the storage landscape can be tricky – especially if you’ve never purchased storage at the business level – or if your business storage needs have recently changed and you’re not sure what to do next.

When it comes to business data storage systems, the major options are direct-attached storage (DAS), network-attached storage (NAS) and storage area networks (SANs). Deciding which is right for your business depends on the following factors.

Key Criteria to Consider:

  • Capacity: How much data do you need to store?
  • Scalability: How much data will you need to store 5 to 10 years from now?
  • Reliability: Can your business survive without its data, files and applications? 
What would downtime do to your business?
  • Backup and Recovery: Where will you back up files and how often? What would 
happen if you lost files?
  • Performance: How many employees need to share/access or collaborate on 
files, from where (remote or in-house) and how often?
  • Budget: How much do you have to spend?
  • IT Staff and Resources: Do you have a dedicated IT staff person to manage your 

DAS — Direct-Attached Storage

Direct-attached storage is a fairly basic, low-maintenance, low-cost solution where the storage system is a part of the actual host computer or connected directly to the host computer. This could be as simple as an external hard drive and it’s the opposite of network storage, where workstations and servers connect through a network. DAS is used in many IT infrastructures and larger DAS storage units can accommodate multiple disks in one enclosure. However, for some business applications requiring greater flexibility and data-sharing across teams, DAS’s ability to grow and scale is limited – especially if you expect to see a lot of business growth over a short period of time.

  • Best Use Case Scenario: DAS is ideal for small businesses that only need to share data locally, have a defined, non-growth budget to work with and have little to no IT support to maintain a complex system.
  • Worst Use Case Scenario: DAS is not a good choice for businesses that are growing quickly, need to scale quickly, need to share across distance and collaborate or support a lot of system users and activity at once.

NAS — Network-Attached Storage

Network-attached storage offers dedicated file serving and sharing through a network. It increases performance and reliability with features like RAID and swappable drives designed for higher multi-drive workloads. NAS storage is also a good solution for consolidating storage systems from DAS – plus, having one centralized, shared storage system will save money in the long run, eliminate confusion and increase reliability in case of system failure or an outage. NAS is known as a top choice for SMBs.

  • Best Use Case Scenario: NAS is perfect for SMBs and organizations that need a minimal-maintenance, reliable and flexible storage system that can quickly scale up as needed to accommodate new users or growing data.
  • Worst Use Case Scenario: Server-class devices at enterprise organizations that need to transfer block-level data supported by a Fibre Channel connection may find that NAS can’t deliver everything that’s needed. Maximum data transfer issues could be a problem with NAS.

SAN — Storage Area Network

A storage area network is a dedicated, high-performance storage system that transfers block-level data between servers and data storage devices. SAN is typically used in data centers, enterprises or virtual computing environments. It offers the speed of DAS with the sharing, flexibility and reliability of NAS. SAN storage is a very sophisticated option that’s meant to support complex, mission-critical applications.

  • Best Use Case Scenario: SAN is best for block-level data sharing of mission- critical files or applications at data centers or large-scale enterprise organizations.
  • Worst Use Case Scenario: SAN can be a significant investment and is a sophisticated solution that’s typically reserved for serious large-scale computing needs. A small-to-midsize organization with a limited budget and few IT staff or resources likely wouldn’t need SAN.

Choosing the best storage option for your business really comes down to deciding which network criteria are most important. Once you know which factors are essential to your business operations, you can find the storage option to fit your particular needs.

Want to learn more about the importance of choosing a reliable storage system? Download the guide, How NAS Can Increase Reliability, Uptime & Data Loss Protection: An IT Executive’s Story.



About the Author:

John Paulsen
John Paulsen is a "Data for Good" advocate, with more than 20 years in the data storage industry. He's helped launch many industry-firsts including HAMR technology, 10K-rpm and 15K-rpm hard drives, drives designed specifically for video and for gaming, Serial ATA drives, fluid dynamic HDD motors, 60TB SSDs, and MACH.2 multi-actuator technology.