SANs offer significant benefits to application performance, scalability, and management. They’re also crucial to meeting today’s business demands for speed and reliability.
SANs take storage devices away from servers, centralizing them into a shared pool that can be accessed through multiple paths for high availability and performance. They often feature RAID and other self-healing technologies to improve efficiency further.
What is a SAN?
Nfina Storage Area Networks (SANs) enable storage traffic to be isolated from server workloads and run on a dedicated network, optimizing performance and accelerating data transfers. This approach reduces storage bottlenecks and frees up server bandwidth, allowing enterprise applications to scale. There are three layers in a Storage Area Network (SAN) infrastructure: the host, fabric, and storage. Centralized management is made more accessible and less expensive, leading to a reduced total cost of ownership. The host layer consists of the servers and their connection to the SAN via an existing LAN or a dedicated fiber application. The fabric layer consists of networking devices, such as switches and directors, connecting hosts to the storage layer. The SAN storage layer includes disk systems and tape libraries that deliver redundancy, scalability, and high availability.
The SAN fabric is a network that connects all the SAN components via Fibre Channel or, in some cases, Ethernet. The SAN network ensures that the storage is always accessible, even in case of a cable or device failure. This redundant architecture makes a SAN ideal for mission-critical applications such as business intelligence, database systems, and e-commerce websites.
SAN Architecture
The SAN architecture sets the stage for data flow, redundancy, and access control. Network topology decisions, such as single or multiple fabrics, switch configurations, and inter-switch links, must consider fault tolerance requirements and expected data traffic patterns. Zoning and Logical Unit Number (LUN) masking strategies determine which servers can access specific storage devices, ensuring security.
A centralized backup system automatically takes over in case of a device failure or network disruption. Most SANs also allow for easy storage capacity expansion without disrupting applications or requiring server reboots.
Centralized storage management simplifies tasks like provisioning, data protection, and snapshotting. It can help organizations achieve regulatory compliance, disaster recovery, and business continuity goals.
Traditional SANs run on high-speed Fibre Channel networks, but newer IP-based fabric protocols offer cost-effective alternatives. These include FCoE (Fibre Channel over Ethernet) and iSCSI, which use SCSI commands inside standard IP packets on a LAN to support block-level transfers at 10GB/sec+.
Vendors are introducing unified SAN/NAS systems that combine file and block storage. Depending on the workload, these typically feature multi-protocol support and allocate physical storage space to NAS or SAN processing. Another trend impacting SAN storage is the movement toward consumption-based IT, where organizations pay for hardware per use rather than buying it outright. This shift to pay-per-use pricing structures can reduce capital expenses and simplify IT operations.
SAN Storage
In a SAN, all storage devices are connected to a dedicated network separate from the traditional LAN. As a result, enterprise workloads can access this collective storage without competing for LAN bandwidth, which can impair performance and cause bottlenecks.
SANs also enable storage traffic to be optimized and accelerated by avoiding the need for data to pass across the LAN. It frees up LAN resources to support other mission-critical applications and servers.
Additionally, the fact that a SAN treats storage as a single collective resource allows administrators to use advanced features like dynamic snapshots to improve data availability. It can help organizations curb application outages caused by individual device or cable failures.
The centralized nature of SAN storage also facilitates a highly efficient backup system. It allows for real-time backups to take place without affecting SAN-connected workloads. Ultimately, this can help organizations achieve better regulatory compliance, disaster recovery (DR), and business continuity postures.
To establish a SAN, map out current and expected server, storage, and application demands. Then, select SAN directors and switches, cabling, Ethernet networking devices, and SAN management software to build a scalable environment that meets your organization’s needs. Install host bus adapters (HBAs) on your physical or virtual servers and rackmount, cable, and configure disk storage arrays to complete the SAN infrastructure.
SAN Management
SAN storage delivers game-changing agility, scalability, and always-on availability for data-intensive applications. It centralizes storage devices and allows centralized backups to mitigate data disruptions. SAN also helps to improve disk utilization by enabling features like thin provisioning, snapshots, and storage cloning.
With a dedicated network fabric, SANs deliver a high level of performance. This is achieved by providing a separate storage network that does not compete for the same bandwidth as the traditional local area network (LAN). SANs are typically deployed with Fibre Channel (FC) for top performance, although iSCSI and converged options are now available.
A SAN can support block, file, and object storage. Most enterprise-class storage is SAN-based.
While SANs are incredibly powerful, they also introduce additional complexity to an IT infrastructure. It includes specialized hardware and cabling, dedicated HBAs on host servers and switches, and a complex fabric layer.
To minimize complexities, running a battery of validation tests and ensuring the SAN functions as intended is crucial. These tests should cover failover behavior, security controls, scalability, and performance. Additionally, a SAN should be monitored over time and expanded to meet business needs. It will prevent overprovisioning, which can waste resources and result in costly data loss. Lastly, a SAN should feature centralized management capabilities to simplify data management and improve storage performance.
