SAN: Whether to go for it or not?

SAN primarily addresses the issues related to large-scale data storage, by enabling access to a central pool of storage resources. SANs are built on the server-attached model via the creation of a separate network of storage devices, independent of the organization's LAN or communications network. You can purchase SAN separate from servers, and allocate and share it as required, over a very fast optical network. SAN can include disk drives, RAID devices, tape libraries, and other storage equipment. Multiple servers— and even client systems— can participate in the storage network to gain access to these devices. The creation of a network of storage devices offers an organization many more options than the traditional approach of connecting storage devices directly to servers.

Looking at the Pros of SAN

The ability to leverage a central pool of intelligent storage to simplify data replication and centralize backup over a fast optical network is a major advantage of a SAN. If we prepare quick pointers for the same we have

• Better Disk Utilization with Centralized Storage
• Reliable DR Solution for multiple applications with quicker back ups
• Continuous Availability of applications
• Higher availability to storage by use of multiple access paths
• Ample free space at disk that defers disk procurement
• Fewer, smaller servers leading to reduced data center rack/floor space
• No distance limits of SCSI-connected disks

Considering the Cons of SAN

• Complex system
• Need to hire technical staff
• Significant Investment in form of fiber optic network and communications equipment
• Inability for multiple servers to attach to the same device for direct file sharing or data-sharing
• Spiraling Cost and Budget
• Few SAN product vendors and very few mega enterprises going for SAN set up

Since the storage area network (SAN) first broke the traditional server/storage bond, some of the storage vendors have dedicated themselves in helping organizations lower their total cost of storage ownership with their collaborative approach to supporting this innovative technology. Through their SAN solutions the technology driven solutions make large storage pools shareable across the enterprise, centralize storage management, and dramatically improve storage utilization, resulting in lower costs.

Get Right Storage Technology for Your Organization

There has recently been a lot of hue and cry around storage issues in networking environments. IT organizations around the world have been struggling to manage, protect and maintain their rapidly growing information assets. Majority of organizations are experiencing data explosion with storage capacity requirements going up to double figure rates. Datacenters across the world continue to face challenges in 2009 as the economy slides downhill -- they are expected to cut costs while providing better performance and improving server and storage utilization rates. Shrinking IT budgets has made the situation grimmer - burdening handful of storage administrators with huge tasks to manage heterogeneous, complex and fast growing data centers. In addition, businesses are subject to a new wave of stringent regulatory compliance legislation that directly affects the process of storing, managing and archiving data. This goes especially for people in financial services and health care industries, who are handling highly sensitive information and maintaining data integrity and privacy.

Getting a control on these issues—while reducing business risk and optimizing storage management costs—requires IT decision makers to take a process- oriented approach to managing their storage, which allows an organization to best meet its overall broad objectives not only from product perspective, implementation perspective but also from aligning the business needs to underlined storage infrastructure. There are a variety of options available, the most prevalent being direct-attached storage (DAS), network-attached storage (NAS) and storage area networks (SAN).

• Direct Attached Storage: Direct-attached storage, or DAS, is the most basic level of storage, where storage devices form a part of the host computer, as with drives, or directly connected to a single server, as with RAID arrays or tape libraries. Here network workstations must access the server in order to connect to the storage device. When considering DAS, it is important to know what your data availability requirements are. DAS is ideal for:
  o Organizations with localized file sharing environments with a single or a few servers
  o Small businesses or workgroups that do not share data over long distances
  o Organizations looking for interim solutions while they plan to migrate to networked storage in the future.
  Limitations:
  o Storage for each server must be administered separately
  o Growing number of servers can lead to management complexity
• Network Attached Storage: NAS was developed to address the challenges inherent in a server- based infrastructure such as direct-attached storage. NAS is file-level computer data storage connected to a computer network providing data access to heterogeneous network clients. NAS is set up with its own network address, rather than being attached to the department computer that is serving applications to a network's workstation users. By removing storage access and its management from the department server, NAS ensures that both application programming and files can be served faster.
  NAS is ideal for
  o Organizations looking for a simple and cost-effective way to achieve fast data access for multiple clients at the file level.
  o Organizations that are small in size
  o Enterprises looking to consolidate their direct-attached storage resources for better utilization
• Storage Area Networks : OFF late, Storage Area Networks (SANs) is being viewed as the most promising class of networked storage - assuring everything from more centralized, simpler storage management to fantabulous reductions in backup windows. With their ability to allow rapid, block level transport and storage of data to a virtual storage "Pool," SANs have appeared to solve most of the issues faced by the IT groups. In a SAN infrastructure, storage devices such as NAS, DAS, RAID arrays or tape libraries are connected to servers using Fibre Channel - an extremely reliable, gigabit interconnect technology that enables simultaneous communication among workstations, mainframes, servers, data storage systems and other peripherals. Without the distance and bandwidth limitations of Small Computer System Interface (SCSI), Fibre Channel is ideal for moving large volumes of data across long distances quickly and reliably.
  
  The strength of SANs lies in its ability to move large blocks of data. This comes especially handy for bandwidth-intensive applications such as database, imaging and transaction processing. SAN dynamically balances loads across the network, and provide swift data transfer while reducing I/O latency and server workload. Your gain is that a large numbers of users can simultaneously access data without choking the local area network and servers.