SAN vs. NAS: Which is Best & Why?

SAN vs. NAS: Which is Best & Why?

Summary: NAS is a file-level server with a single storage device storing and sharing files over Ethernet. At the same time, SAN is block-level storage built up of multiple drives, a Fibre Channel network, and a separate Ethernet. While deciding which one to choose, you must consider a number of factors. In this article, we’ve given a detailed comparison, showing the performance output, price, scalability, and several other factors.

There are many factors to consider while comparing SAN with NAS. Storage Area Network or SAN is a block-level storage engineered to deliver high performance for mission-critical applications. Conversely, NAS is a file-level server that makes data constantly available for its users to store and share easily.

Both these technologies aim to make data available to multiple people simultaneously. However, how they both achieve that goal is a bit different. Continue reading this article to know more about SAN and NAS!

What is SAN?

SAN or Storage Area Network is engineered to deliver high performance for consolidated block-level storage and mission-critical applications. It connects multiple storage drives, like tape libraries and disk drives, switches, and hosts, to a dedicated network separate from the primary LAN (Local Area Network).

SAN uses protocols like SATA, FCP iSCSI, FCoE, and FC-NVMe. It offers users shared access to the block-level, consolidated storage. SAN volumes appear and perform as a locally attached storage by joining SAN server, multiple clients, and storage on a FC network. High-end enterprise SAN setups can even include SAN directors to deliver efficient capacity usage and higher performance.

What is NAS?

NAS stands for Network Attached Storage, a file-level data storage architecture that provides a single access point for people to store and share their files between the networked devices easily. This storage device is easy to set up and deploy, combining hardware and software.

It usually contains one or more hard drives, often configured into RAID. Users see the NAS volumes as network-mounted volumes and use them to store especially unstructured data, such as images, documents, PPTs, spreadsheets, and more. It employs protocols like Network File System, Server Message Block SMB/CIFS, and HTTP.

Head units like Memory and CPU manage NAS devices. It additionally contains a web portal interface or client portal and services, such as Synology’s Hyper Backup, QNAP’s Hybrid Backup Sync, etc., to help manage the files.

SAN vs. NAS – Features Wise Comparison

Below, we’re sharing a detailed comparison between NAS and SAN, keeping their data storage architecture, protocols, etc.

Data Storage

Storage Area Network processes data using a block-by-block copying technique, while Network-Attached storage processes file-based data. SAN provides direct access to consolidated block-level storage, while NAS offers access to files and folders. Additionally, NAS server may operate with a global namespace that combines several NAS devices to show a consolidated view of data storage. On the other hand, SAN has access to a specialized SAN file system that enables servers to share files.

Do you know?

A global namespace is a group of file systems from different file storage devices, like servers using CIFS (common Internet file system), NFS (network file system), NAS (network-attached storage), or File servers.

Protocols

NAS connects directly to the Ethernet network via a LAN cable to an Ethernet switch. Conversely, SAN combines client OS, servers, and storage on an FC (Fibre Channel) network. For higher performance, it may also require a private Ethernet network between servers and clients to keep the file request traffic out of the FC network. To connect with servers, NAS may use protocols like NFS, CIFS/SMB, and HTTP. However, servers and SAN drives communicate in SAN using iSCSI, FCB, FCoE, and NVMe protocols.

Fabric Protocol

Important: Network Fabric is an area of the network that connects network devices, like access points, routers, and switches that transports data to its destination.

NAS is a network node like systems and other TCP/IP devices that maintain IP addresses. The NAS file service also uses the Ethernet network to send and receive the files. On the contrary, traditional SAN configurations run on high-speed FC (Fibre Channel) Networks. However, multiple SAN configurations adopt the IP-based fabric protocols due to the FC’s expense and complexity. Flash-based fabric protocols are becoming very useful in meeting the high-performance requirement of SANs to close the gap between FC speeds and slower IPs.

Scalability

Scalability is one of the primary strengths of SANs. Its network architecture allows administrators to scale the capacity and performance in scale-out or scale-up configurations without affecting network integrity. On the contrary, entry-level NAS servers are not highly scalable. However, high-end NAS systems scale to petabytes using the scale-out nodes or clusters

Speed & Performance

SAN provides a separate storage-based network for block data over FC. Users see SAN as external drives on their local system and can easily access the disk arrays and tape libraries configured in SAN. It delivers higher speed for media and mission-critical applications—environments requiring high-speed traffic and transaction databases like e-commerce websites. NAS, on the other side, has lower throughput and higher latency due to the slower file system layer and dependency on the TP/IP, usually Ethernet networks (100 MB to 1GB/minute). However, high-speed LANs can overcome most performance losses.

Deployment & Management

While comparing SAN vs. NAS, NAS takes the primary spot in the ease of deployment and management areas. NAS is a single device setup that you need to plug into the LAN, and it will serve the files over Ethernet, enabling simplified management. SAN, as compared to NAS, needs more administration time. It is a tightly coupled network of many devices working with block-based data. It additionally requires a separate Ethernet network to handle metadata file requests. It also needs physical changes to the data center in SAN deployment, along with the ongoing management needs of specialized administrators.

Price

SANs are expensive and complex to set up and manage compared to NAS devices since they require multiple devices, client OS, and a separate Ethernet combined with an FC network. However, NAS is cheaper to purchase and maintain since it requires fewer hardware and software management components. Furthermore, administration costs figures into the equation.

Limitations of NAS vs. SAN

Let’s shed some light on the limitations of both these storage technologies!

NAS Limitations

Lower Scalability & Performance

The primary disadvantage of NAS devices is their performance and scalability. As the number of people accessing NAS increases, the server may be unable to keep up with the speed and raise latency (slow or retired connection) issues. Additionally, entry-level NAS devices (usually configured with a single hard drive) are not highly scalable.

Scope for Data Loss

Another primary disadvantage of entry-level NAS (built with a single hard drive or RAID 0) is that it is not as secure as other storage drives like RAID levels (RAID 1, 5, or 6). If NAS drives fail, controller malfunction, or human error occurs, you may lose your data. However, you may use an advanced data recovery solution, such as Raminfotech Toolkit for Data Recovery to recover data from NAS quickly. In case of backup unavailability and server downtime, your data remains at risk in NAS.

Limited Support Availability

Moreover, some NAS devices may not be compatible with your existing IT infrastructure, which leads to a lack of support if you need to troubleshoot or maintain the system.

SAN limitations

Complexity

SAN is a complex setup to deploy and manage, requiring client OS, SAN server, and storage on a Fibre Channel network with an additional Ethernet network to keep the traffic out of the FC network for higher performance. These things make SAN a desirable option in terms of performance and, simultaneously, make it a little complex for users who need more technical expertise.

Privacy

Since SAN is used in a shared environment, there remains a possibility of data leakage despite the proper security measures. Storage drives and servers are accessed by other connected systems, which may make you a victim of system hacking, identity theft, data leak, or other threats.

Data Loss:

Similar to NAS, SAN is also prone to experience data loss. Out of all, hardware failure is the most common reason for data loss in SAN devices. Other reasons that may contribute to data loss include software and firmware corruption, malware attacks, power failure, etc. Data recovery, however, can be a bit challenging compared to NAS as it usually contains HDDs or SSDs, but is possible.

When should you use NAS and SAN?

Use NAS when…

Your focus is on centralized, consolidated file storage and sharing. This is why NAS is preferred in home environments and small to medium-sized businesses. It offers multiple file servers ease of management, space, and energy savings. Additionally, NAS for virtualization networks is also becoming useful for small virtualization environments since VMware and Hyper-V support their database on NAS.

Use SAN when…

You want to scale and accelerate in the high-speed transactional environment with high I/O processing speed and lower latency (slow or retired connection) issues. SAN is best for professional and enterprise environments. NAS for virtualization networks is getting popular. However, for large-scale and high-performance deployments, SAN is the better fit. Additionally, SAN is visible to the server OS as attached storage. Hence, it enables fast backup.

What to choose- NAS or SAN?

Remember the fundamental differences while deciding whether to choose SAN or NAS. Where NAS is easier to set up and manage and a good option for home, SME general-purpose applications, SANs are great for large-scale environments where speed, high-performance, and low latency issues are required.

Moreover, some vendors are encouraged by the benefits of SANs and are looking forward to offering SAN-like products at affordable costs by removing the high cost of the FC network. This initiative has brought up the partial convergence of the SAN vs. NAS approach to network storage available at cost-effective prices than a dedicated SAN.

SAN vs. NAS: Which is Best & Why?

What is SAN?

What is NAS?

SAN vs. NAS – Features Wise Comparison