Storage Area Networks

A Storage Area Network (SAN) is a specialized network architecture that provides block-level storage access to servers and applications. SANs are typically used to provide high-speed, scalable storage for mission-critical applications, such as databases, email servers, and virtualized environments.

SANs use specialized hardware and software to provide storage connectivity between servers and storage devices. SANs typically use Fibre Channel (FC) or iSCSI protocols to provide high-speed, low-latency storage access. SANs can be configured in several topologies, including switched fabric, arbitrated loop, and point-to-point connections.

Some of the advantages of SANs include:

High performance: SANs can provide high-speed storage access, with low latency and high throughput, which can be critical for mission-critical applications.

Scalability: SANs can be scaled up to meet growing storage demands, by adding additional storage devices or expanding the network infrastructure.

Data protection: SANs can provide built-in data protection features, such as RAID, replication, and snapshotting, which can help ensure data availability and protect against data loss in case of hardware failures or other disasters.

Centralized management: SANs provide centralized storage management, which can simplify storage administration, backup and restore operations, and data migration.

However, SANs also have some potential disadvantages, including:

Complexity: SANs can be complex to configure and manage, and may require specialized expertise. Careful planning and configuration is required to ensure that the SAN solution is optimized for the specific workload and data access patterns.

Cost: SANs can be expensive, especially when high-performance or high-availability features are required. Organizations should carefully evaluate the cost of SAN solutions against the benefits they provide before implementing them as a storage solution.

Network dependency: SANs rely on network connectivity to access storage devices, which can make them vulnerable to network congestion or failures. This can result in reduced performance or data unavailability.

Security: SANs can be vulnerable to network-based attacks, such as data interception or unauthorized access. Implementing strong security measures, such as network encryption and access control, is critical to protecting data stored on SANs

With the rapid growth of electronic commerce, the Enterprise Resource Planning system that basically integrates application data across the organization, and data warehouses that keep historical aggregate information, the demand for storage has to go up substantially. For today’s Internet Driven organization, it has become necessary to move from a static fixed data center oriented operation to a more flexible and dynamic infrastructure for their information processing requirements. Many users of RAID system cannot use the capacity effectively because it has to be attached to a concept called Storage Area Network (SAN). In a SAN, online storage peripherals are configured as nodes on a high-speed network and can be attached and de-attached from servers in a very flexible manner. Many companies have come up as SAN providers and provide their own proprietary topologies. They basically allow storage systems to be placed at the longer distance from the servers and provide different performance and connectivity options. Existing storage management applications can be ported into SAN configuration using Fibre Channel networks that encapsulate the legacy SCSI protocol. As a outcome of which the SAN-attached devices appear as SCSI devices. Current architectural alternatives for SAN include the following:

1. Point to point connection between the storage system and servers via Fibre Channel.
2. Use of Fibre Channel switches to connect Multiple RAID systems, tape libraries and so on to servers.
3. Use of Fibre Channel hubs and switches to connect servers and storage system in the different configuration.

Main advantages claimed are following:

1. Flexible for many to many connectivity among servers and storage device with the help of fibre channel hubs and switches.
2. Up to 10 Km separation between a server and a storage system using appropriate fibre optic cables.
3. Better isolation capabilities allowing the nondisruptive addition of new servers and peripherals.

Use of SANs are increasing rapidly but it still facing many problems such as combining storage option from multiple vendors and dealing with evolving standards of storage management software and hardware. Most major companies are evaluating SAN as a viable option for database storage.

My Personal Notes arrow_drop_up

Save