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NETWORK ATTACHED STORAGE DIFFERENT FROM
TRADITIONAL FILE SERVERS & IMPLEMENTATION OF
WINDOWS BASED NAS
Nathwani Namrata
Lecturer in Government Polytechnic, Rajkot
ABSTRACT
Several new methods of utilizing computer networks for data storage have emerged in recent years. One popular approach, Network Attached Storage (NAS), allows homes and businesses to store and retrieve large amounts of data more affordable than ever before. Network attached storage (NAS) is file-level computer data storage connected to a computer network providing data access to heterogeneous clients. Network Attached Storage is designed to separate storage resources from network and application servers in order to simplify storage management and improve the reliability, performance and efficiency of the network, thus increasing the overall productivity of the organization.
Network Attached Storage servers are self-contained, intelligent devices that attach directly to your existing LAN. This intelligence on the NAS device enables true data sharing among heterogeneous network clients. NAS unit is a computer connected to a network that only provides file-based data storage services to other devices on the network. So NAS is useful for more than just general centralized storage provided to client computers in environments with large amounts of data.
Keywords: Network Attached Storage (NAS), Storage Devices, Difference among Direct Attached Storage (DAS), Storage Area Network (SAN) and Network Attached Storage (NAS).
1. Windows based Storage Devices
1. INTRODUCTION
Network Attached Storage, or NAS, is a data storage mechanism that uses special devices connected directly to the network media. These devices are assigned an IP address ISSN 0976 – 6367(Print)
ISSN 0976 – 6375(Online)
Volume 4, Issue 3, May-June (2013), pp. 539-549
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and can then be accessed by clients via a server that acts as a gateway to the data or in some cases allows the device to be accessed directly by the clients without an intermediary.
The beauty of the NAS structure is that it means that in an environment with many servers running different operating systems, storage of data can be centralized, as can the security, management, and backup of the data.
Some of the big advantages of NAS include the expandability; need more storage space, add another NAS device and expand the available storage. NAS also bring an extra level of fault tolerance to the network. In a DAS environment, a server going down means that the data that that server holds is no longer available. With NAS, the data is still available on the network and accessible by clients. Fault tolerant measures such as RAID, which, can be used to make sure that the NAS device does not become a point of failure.
A NAS unit is a computer connected to a network that only provides file-based data storage services to other devices on the network. Although it may technically be possible to run other software on a NAS unit, it is not designed to be a general purpose server. For example, NAS units usually do not have a keyboard or display, and are controlled and configured over the network, often using a browser.
Fig -1 Network attached storage
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2. HOW TO WORK
Like traditional file servers, NAS follows a client/server design. A single hardware device, often called the NAS box or NAS head, acts as the interface between the NAS and network clients. These NAS devices require no monitor, keyboard or mouse. They generally run an embedded operating system rather than a full-featured NOS. One or more disk (and possibly tape) drives can be attached to many NAS systems to increase total capacity. Clients always connect to the NAS head, however, rather than to the individual storage devices.
Clients generally access a NAS over an Ethernet connection. The NAS appears on the network as a single "node" that is the IP address of the head device.
A NAS can store any data that appears in the form of files, such as email boxes, Web content, remote system backups, and so on. Overall, the uses of a NAS parallel those of traditional file servers.
NAS systems strive for reliable operation and easy administration. They often include built-in features such as disk space quotas, secure authentication, or the automatic sending of email alerts should an error be detected.
Fig-3 Working of NAS topology
3. ADVANTAGES OF NAS
1) Multiple users can access the drive at the same time. 2) Files can be shared among users and devices. 3) Remote access via Ethernet is possible.
4) Availability of data might potentially be increased with NAS if it provides built-in RAID and clustering capabilities.
4. DRAWBACKS
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2) Management is still an issue, although less so than a few years ago. While storage management facilities on NAS filers have gotten a lot better, especially with the release of Windows Storage Server, NAS filers still lack the sophisticated management tools available for SANs or high-end NAS systems. Today, most NAS filers have Web-based interfaces that allow them to be managed with a browser. Even inexpensive NAS filers often include features such as snapshots, checkpoints and journaling file systems to improve data integrity. 3) Backup is also a consideration. Some filers back up to an attached tape drive or library, while others can be backed up over the network. Backing up to a separate device introduces some complexity in managing backups. Backing up over the network puts an additional load on the network.
5. NAS vs. TRADITIONAL FILE SERVERS
Proponents of NAS claim that NAS technology provides these advantages over traditional file servers:
1) Lower cost. 2) Better security.
3) Higher availability (less downtime). 4) Easier to use and administer.
6. DIFFERENCE AMONG DIRECT ATTACHED STORAGE, STORAGE AREA NETWORK & NETWORK ATTACHED STORAGE
1) Direct Attached Storage (DAS)
Direct attached storage is the term used to describe a storage device that is directly attached to a host system. The simplest example of DAS is the internal hard drive of a server computer
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Fig 5 Direct attached storage connected with clients 2) Storage Area Network (SAN)
A SAN is a network of storage devices that are connected to each other and to a server, or cluster of servers, which act as an access point to the SAN. In some configurations a SAN is also connected to the network. SAN's use special switches as a mechanism to connect the devices. These switches, which look a lot like a normal Ethernet networking switch, act as the connectivity point for SAN's. Making it possible for devices to communicate with each other on a separate network brings with it many advantages.
544 3) Network Attached Storage (NAS)
Network Attached Storage, or NAS, is a data storage mechanism that uses special devices connected directly to the network media. These devices are assigned an IP address and can then be accessed by clients via a server that acts as a gateway to the data or in some cases allows the device to be accessed directly by the clients without an intermediary.
Fig-7 Network attached storage in LAN 7. WINDOWS BASED NETWORK ATTACHED STORAGE
Current offerings in the Network-Attached Storage (NAS) market generally fall into two camps – the Windows-based NAS solutions and NAS solutions based on other operating systems and macrocodes. Windows Powered Network Attached Storage (NAS) is an optimized file server based on Windows technology that is designed for high reliability, availability, and ease of management. Windows Powered NAS integrates with the existing infrastructure and supports heterogeneous file serving as well as backup/replication of mission-critical data. Windows Powered NAS is also an ideal solution for consolidating multiple file servers into a single solution that enables cost reduction and policy-based management of storage resources. Windows Powered NAS includes advanced availability features such as point-in-time data copies, replication, and server clustering. Because Windows Powered NAS solutions are preconfigured, they can be deployed out of the box in minutes, and their Web user interface makes management easy. Windows Powered NAS integrates with existing infrastructures, so enterprises can leverage commonly used network environments and standard management software, as well as Windows 2000 Server’s Active Directory service. Preconfigured Windows Powered NAS solutions are available from industry leading OEMs in sizes ranging from a few hundred gigabytes to several terabytes.
The Windows-based NAS solutions are built with Microsoft-qualified server hardware running Microsoft Windows Storage Server 2003, which is based on Windows Server 2003 technology and optimized for serving networked storage.
545 Technical
scenario Business needs Why windows powered NAS File serving A. High reliability
B. High availability C. Easy of management D. Integration into existing infrastructure
A. Optimized for File Serving
B. No overhead of running applications C. Replace multiple GP servers used for file
serving with single solution
Backup/Restore and Replication A. Business continuity • Disaster recovery • Availability of data
A. Backup without taking Servers offline B. Geographic Replication Server consolidation A. Optimize IT resources • Lower touch point • Reduce admin cost A. Low $/MB
B. Consolidate multiple file servers C. More data per server per admin
Table-1 Benefits for using windows powered NAS 8. KEY TECHNOLOGY IN WINDOWS BASED NAS
A. Highly reliable & Available 1) Optimized software and hardware:
Access stored files with more reliability using a Windows operating system that is optimized for file serving. In addition, built-in hardware redundancies are included in the solution to avoid any single points of failure within the device.
2) Persistence storage manager:
Provide high data availability by creating and managing up to 250 data snapshots.
Entire server volumes of corrupted or deleted data can be restored within minutes, instead of hours that might be required to restore from tape.
3) Storage manager:
Optimize storage resources by setting quotas at volume, directory, and user levels. In addition, enforce rules regarding storage of unwanted files by filtering file types and track resource usage with storage reports.
4) Distributed file system:
Build and manage a single, hierarchical view of multiple file servers and their shares.
Distributed File System (DFS) simplifies management of data on multiple distributed servers. DFS enables Windows Powered NAS to automatically redirect clients to data replicas in case data becomes unavailable.
5) Clustering:
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Increase data availability and provide disaster recovery by creating multiple copies of data on remote servers over local area networks (LANs) or wide area networks (WANs) using third party add-on software.
B. Easy to deploy and manage 1) Plug-and-play deployment:
Deploy a preconfigured Windows Powered NAS solution in minutes. Use a Web interface to connect to the network, join an Active Directory domain or a local workgroup, add users, create shares, and select file sharing tools.
2) Remote manager:
Manage devices remotely through a Web user interface, Terminal Services, or standard enterprise server management tools.
C. Seamless Enterprise Integration 1) Active directory integration:
Take advantage of existing Active Directory policies to centrally manage Windows Powered NAS using Group Policy, Kerberos Authentication, and Encrypted File System.
2) Network interoperability:
Easily configure Windows Powered NAS to interoperate with most common network environments, including Windows, UNIX, Novell NetWare, and Apple Macintosh. Also included is support for CIFS, FTP, WebDAV, and Apple File Sharing Services.
3) Support for existing management software:
Leverage existing IT investment in server management tools like Microsoft Systems Management Server, Tivoli, and HP Open View.
4) ANTI-VIRUS SOFTWARE SUPPORT
Take advantage of investment in existing anti-virus utilities to protect data. D. Low Total Cost of Ownership
Windows Powered NAS enables IT administrators to easily manage growing amounts of data while reducing storage costs. Customers can acquire Windows Powered NAS at one of the lowest costs per gigabyte available, and take advantage of high scalability to expand storage capacity as needed.
Advanced availability features, ease of deployment and management, and seamless enterprise integration also combine to lower the total cost of ownership
E. File Level Security
NTFS enables the administrator to put security access control lists on each directory and file, such that individuals and groups have specific privileges.
F. File Sharing/Locking
Individuals or applications can open a file for reading while another user or application is writing to it elsewhere.
G. Encrypted File System
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Enables system administrators to monitor disk space usage to ensure that systems do not unexpectedly reach capacity. Capacity can be monitored by both volumes and users. In addition, enforce rules regarding storage of unwanted files by filtering file types and track resource usage with storage reports.
9. NAS SERVER
NAS servers are dedicated (and often optimized) file servers that function to store and retrieve files for production servers. Whereas general-purpose production servers are loaded with applications that consume storage, NAS servers are stripped of unnecessary hardware (there is no monitor, keyboard or mouse) and software applications, and use only those components of the operating system required for file serving, thus maximizing the disk space available for storage.
NAS Server has several advantages A. Rapid Installation
NAS appliances are preconfigured with the necessary software for effective existing network. Unlike general-purpose servers which can be complex and time-consuming to install, often requiring network downtime, NAS servers can be plugged directly into the network cable—with no impact on network operations—configured and up and running in less than 15 minutes. All NAS server management is conducted through a web browser interface, rather than having to use the command line interface more common to general-purpose servers.
B. Support for Heterogeneous Environments
NAS servers make pooled storage available to multiple operating systems, thus making it unnecessary to maintain multiple machines for separate storage, lowering costs and streamlining management. Windows Powered NAS servers from Dell support CIFS and NFS file sharing protocols (among others) enable file serving of both Windows and Unix files. C. Server Consolidation
By shifting the file serving and storage burden off of the general-purpose servers onto high storage capacity NAS servers, overall equipment costs and associated licensing expenses decline. Moreover, pooling storage on a NAS server both makes it both simpler for users to access files as well as streamlining storage management
D. Improved Server Performance
Production servers relieved of the burden of file serving, experience less bandwidth congestion and improved performance, which translates directly into improved response time for the end users.
E. Highly Available Data
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ensures that in the event of storage problems, the production servers remain online. Conversely, should there be a problem with a production server; files are still available through the NAS device.
10. DEPLOYMENT SCENARIO A. File serving
1) Pre-configured for easy deployment 2) Designed for remote management 3) Dedicated optimized file server
4) Data protection with Persistent Storage Manager
Fig-8 File serving B. Backup & replication
NAS used for network backup from multiple production servers 1) NAS may be clustered for added availability
2) Production servers don’t have to be taken offline 3) Replication increases data and device availability
Fig-9 Backup & replication
C. Server consolidation
1) Reduce number of servers on the network 2) Lower cost of storage management 11. CONCLUSION
Windows Powered NAS provides both robust file serving and backup capabilities, thereby enabling both server and tape device equipment consolidation. The NAS server is an out-of-the-box solution that can be deployed in minutes, without network downtime. The minimal management of NAS servers can be accomplished through a web browser, rather than having to use command-line interfaces. NAS servers provide simple cross
sharing and backups, greatly simplifying management of multiple platforms, makin necessary and valuable part of your complete enterprise backup solution.
12. REFERENCES
[1] http://www.microsoft.com/storage [2] http://en.wikipedia.org/wiki/Network
[3] Cyju Varghese, John Blesswin, Navitha Varghese Approach for Satellite Imagery Storage
International Journal of Computer Engineering & Technology (IJCET), Volume Issue 2, 2012, pp. 147 - 159
[4] Prof. S.A.Ubale and Dr. S.S. Apte
with .Net Framework for Windows Operating System Computer Engineering & Technology (IJCET), Volume pp. 426 - 434, ISSN Print: 0976
549
Fig -10 server consolidation Reduce number of servers on the network
Lower cost of storage management
Windows Powered NAS provides both robust file serving and backup capabilities, thereby enabling both server and tape device equipment consolidation. The NAS server is an box solution that can be deployed in minutes, without network downtime. The minimal management of NAS servers can be accomplished through a web browser, rather
line interfaces. NAS servers provide simple cross
sharing and backups, greatly simplifying management of multiple platforms, makin necessary and valuable part of your complete enterprise backup solution.
http://www.microsoft.com/storage
http://en.wikipedia.org/wiki/Network-attached_storage
Cyju Varghese, John Blesswin, Navitha Varghese and Sonia Singha,
or Satellite Imagery Storage by Classifying the Non-Duplicate Regions ournal of Computer Engineering & Technology (IJCET), Volume
159, ISSN Print: 0976 – 6367, ISSN Online: 0976
Dr. S.S. Apte, “Study and Implementation of Code Access Security or Windows Operating System”, International
Computer Engineering & Technology (IJCET), Volume 3, Issue , ISSN Print: 0976 – 6367, ISSN Online: 0976 – 6375.
Windows Powered NAS provides both robust file serving and backup capabilities, thereby enabling both server and tape device equipment consolidation. The NAS server is an box solution that can be deployed in minutes, without network downtime. The minimal management of NAS servers can be accomplished through a web browser, rather line interfaces. NAS servers provide simple cross-platform file sharing and backups, greatly simplifying management of multiple platforms, making it a
ingha,, “A Novel Duplicate Regions”, ournal of Computer Engineering & Technology (IJCET), Volume 1,
6367, ISSN Online: 0976 – 6375. f Code Access Security International Journal of
