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NAS Storage

NAS Storage

NAS Storage

 

Network-attached storage (NAS) is file-level computer data storage connected to a computer network providing data access to aheterogeneous group of clients. NAS not only operates as a file server, but is specialized for this task either by its hardware, software, or configuration of those elements. NAS is often manufactured as a computer appliance – a specialized computer built from the ground up for storing and serving files – rather than simply a general purpose computer being used for the role.

As of 2010 NAS devices are gaining popularity, as a convenient method of sharing files among multiple computers. Potential benefits of network-attached storage, compared to file servers, include faster data access, easier administration, and simple configuration.

Network-attached storage
Connects to Local Area Network via one of:

  • Ethernet
  • Wi-Fi

Hard Drives via one of:

  • SATA
  • SAS
  • USB
Common manufacturers EMC Corporation
NetApp
HP
Buffalo Technology
Netgear
Sun Microsystems
LaCie
Introduced 1980s

Description

A Netgear NAS

A NAS unit is a computer connected to a network that provides only 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.

Description
A Netgear NAS
A NAS unit is a computer connected to a network that provides only 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.

A full-featured operating system is not needed on a NAS device, so often a stripped-down operating system is used. For example, FreeNAS, an open source NAS solution designed for commodity PC hardware, is implemented as a stripped-down version of FreeBSD.

NAS systems contain one or more hard drives, often arranged into logical, redundant storage containers or RAID.

NAS uses file-based protocols such as NFS (popular on UNIX systems), SMB/CIFS (Server Message Block/Common Internet File System) (used with MS Windows systems), AFP (used with Apple Macintosh computers), or NCP (used with OES and Novell NetWare). NAS units rarely limit clients to a single protocol.

A full-featured operating system is not needed on a NAS device, so often a stripped-down operating system is used. For example,FreeNAS, an

Description
A Netgear NAS
A NAS unit is a computer connected to a network that provides only 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.[4]

A full-featured operating system is not needed on a NAS device, so often a stripped-down operating system is used. For example, FreeNAS, an open source NAS solution designed for commodity PC hardware, is implemented as a stripped-down version of FreeBSD.

NAS systems contain one or more hard drives, often arranged into logical, redundant storage containers or RAID.

NAS uses file-based protocols such as NFS (popular on UNIX systems), SMB/CIFS (Server Message Block/Common Internet File System) (used with MS Windows systems), AFP (used with Apple Macintosh computers), or NCP (used with OES and Novell NetWare). NAS units rarely limit clients to a single protocol.

 NAS solution designed for commodity PC hardware, is implemented as a stripped-down version of FreeBSD.

NAS systems contain one or more hard drives, often arranged into logical, redundant storage containers or RAID.

NAS uses file-based protocols such as NFS (popular on UNIX systems), SMB/CIFS (Server Message Block/Common Internet File System) (used with MS Windows systems), AFP (used with Apple Macintosh computers), or NCP (used with OES and Novell NetWare). NAS units rarely limit clients to a single protocol.

NAS vs. DAS

The key difference between direct-attached storage (DAS) and NAS is that DAS is simply an extension to an existing server and is not necessarily networked. NAS is designed as an easy and self-contained solution for sharing files over the network.

Both DAS and NAS can potentially increase availability of data by using RAID or clustering.

NAS vs. SAN

Visual differentiation of NAS vs. SANuse in network architecture

NAS provides both storage and a file system. This is often contrasted with SAN (Storage Area Network), which provides only block-based storage and leaves file system concerns on the “client” side. SAN protocols include Fibre Channel, iSCSI, ATA over Ethernet (AoE) andHyperSCSI.

Implementation

The way manufacturers make NAS devices can be classified into three types:

  1. Computer based NAS – Using a computer (Server level or a personal computer), installs FTP/SMB/AFP… software server. The power consumption of this NAS type is the largest, but its functions are the most powerful. Some large NAS manufacturers like QNAP, Synology and ASUStor make these types of devices. Max FTP throughput speed varies by computer CPU and amount of RAM.
  2. Embedded system based NAS – Using an ARM, MIPS… embedded system and RTOS to run a NAS server. The power consumption of this NAS type is fair, and functions in the NAS can fit most end user requirements. Marvell, Oxford, and Storlink make chipsets for this type of NAS. Max FTP throughput varies from 20 MB/s to 120 MB/s.
  3. ASIC based NAS – Provisioning NAS through the use of a single ASIC chip, using hardware to implement TCP/IP and file system. There is no OS in the chip, as all the performance-related operations are done by hardware acceleration circuits. The power consumption of this type of NAS is low, as functions are limited to only support SMB and FTP. Layerwalker is the only chipset manufacturer for this type of NAS. Max FTP throughput is 40 MB/s.

Uses

NAS is useful for more than just general centralized storage provided to client computers in environments with large amounts of data. NAS can enable simpler and lower cost systems such as load-balancing and fault-tolerant email and web server systems by providing storage services. The potential emerging market for NAS is the consumer market where there is a large amount of multi-media data. Such consumer market appliances are now commonly available. Unlike their rackmounted counterparts, they are generally packaged in smaller form factors. The price of NAS appliances has plummeted in recent years, offering flexible network-based storage to the home consumer market for little more than the cost of a regular USB or FireWire external hard disk. Many of these home consumer devices are built around ARM, PowerPC or MIPS processors running an embedded Linux operating system.

Examples

Open source server implementations

Open source NAS-oriented distributions of Linux and FreeBSD are available, including FreeNAS, NAS4Free, CryptoNAS, NASLite, Gluster, Openfiler, OpenMediaVault, EasyNASand the Debian-based TurnKey File Server. These are designed to be easy to set up on commodity PC hardware, and are typically configured using a web browser.

They can run from a virtual machine, Live CD, bootable USB flash drive (Live USB), or from one of the mounted hard drives. They run Samba (an SMB daemon), NFS daemon, and FTP daemons which are freely available for those operating systems.

NexentaStor, built on the Nexenta Core Platform, is similar in that it is built on open source foundations; however, NexentaStor requires more memory than consumer-oriented open source NAS solutions and also contains most of the features of enterprise class NAS solutions, such as snapshots, management utilities, tiering services, mirroring, and end-to-end checksumming due, in part, to the use of ZFS.

List of network protocols used to serve NAS

  • Andrew File System (AFS)
  • Apple Filing Protocol (AFP)
  • Server Message Block (CIFS, former SAMBA)
  • File Transfer Protocol (FTP)
  • Hypertext Transfer Protocol (HTTP)
  • Network File System (NFS, a UNIX protocol)
  • rsync
  • SSH file transfer protocol (SFTP)
  • Universal Plug and Play (UPnP)

Web User Interface,
Command Line Interface,
10GigE Drivers,
Thin Provisioning,
Zettabyte File System,
Snapshots,
Backup and Restore,
File Sharing,

File Server

File Server

In computing, a file server is a computer attached to a network that has the primary purpose of providing a location for shared disk access, i.e. shared storage of computer files (such as documents, sound files, photographs, movies, images, databases, etc.) that can be accessed by the workstations that are attached to the same computer network. The term server highlights the role of the machine in the client–server scheme, where the clients are the workstations using the storage. A file server is not intended to perform computational tasks, and does not run programs on behalf of its clients. It is designed primarily to enable the storage and retrieval of data while the computation is carried out by the workstations.

File servers are commonly found in schools and offices, where users use a LAN to connect their client computers.

Types of file servers

A file server may be dedicated or non-dedicated. A dedicated server is designed specifically for use as a file server, with workstations attached for reading and writing files and databases.

File servers may also be categorized by the method of access: Internet file servers are frequently accessed by File Transfer Protocol (FTP) or by HTTP (but are different from web servers, that often provide dynamic web content in addition to static files). Servers on a LAN are usually accessed by SMB/CIFS protocol (Windows and Unix-like) or NFS protocol (Unix-like systems).

Database servers, that provide access to a shared database via a database device driver, are not regarded as file servers as they may require Record locking.

Design of file servers

In modern businesses the design of file servers is complicated by competing demands for storage space, access speed, recoverability, ease of administration, security, and budget. This is further complicated by a constantly changing environment, where new hardware and technology rapidly obsolesces old equipment, and yet must seamlessly come online in a fashion compatible with the older machinery. To manage throughput, peak loads, and response time, vendors may utilize queuing theory to model how the combination of hardware and software will respond over various levels of demand. Servers may also employ dynamic load balancing scheme to distribute requests across various pieces of hardware.

The primary piece of hardware equipment for servers over the last couple of decades has proven to be the hard disk drive. Although other forms of storage are viable (such asmagnetic tape and solid-state drives) disk drives have continued to offer the best fit for cost, performance, and capacity.

Storage

Since the crucial function of a file server is storage, technology has been developed to operate multiple disk drives together as a team, forming a disk array. A disk array typically has cache (temporary memory storage that is faster than the magnetic disks), as well as advanced functions like RAID and storage virtualization. Typically disk arrays increase level of availability by using redundant components other than RAID, such as power supplies. Disk arrays may be consolidated or virtualized in a SAN.

Network-attached storage

Main article: Network-attached storage

Network-attached storage (NAS) is file-level computer data storage connected to a computer network providing data access to heterogeneous clients. NAS devices specifically are distinguished from file servers generally in a NAS being a computer appliance – a specialized computer built from the ground up for serving files – rather than a general purpose computer being used for serving files (possibly with other functions). In discussions of NASs, the term “file server” generally stands for a contrasting term, referring to general purpose computers only.

As of 2010 NAS devices are gaining popularity, offering a convenient method for sharing files between multiple computers. Potential benefits of network-attached storage, compared to non-dedicated file servers, include faster data access, easier administration, and simple configuration.

NAS systems are networked appliances containing one or more hard drives, often arranged into logical, redundant storage containers or RAID arrays. Network Attached Storage removes the responsibility of file serving from other servers on the network. They typically provide access to files using network file sharing protocols such as NFS, SMB/CIFS (Server Message Block/Common Internet File System), or AFP.

Security

File servers generally offer some form of system security to limit access to files to specific users or groups. In large organizations, this is a task usually delegated to what is known as directory services such as openLDAP, Novell’s eDirectory or Microsoft’s Active Directory.

These servers work within the hierarchical computing environment which treat users, computers, applications and files as distinct but related entities on the network and grant access based on user or group credentials. In many cases, the directory service spans many file servers, potentially hundreds for large organizations. In the past, and in smaller organizations, authentication could take place directly at the server itself.

Centralised Data Management,
Windows AD like Features,
Group Policies,
Ldap,
MySQL,
Windows AD integration,
Logon Scripts,
MIME protection,
Unlimited Users,
Easy Control Panel,
Compatible with windows desktops,
Roaming Profile,

Squid Proxy Server

Squid Proxy Server

Squid Proxy Server

 

Proxy server

Diagram of two computers connected only via a proxy server. The first computer says to the proxy server: "ask the second computer what the time is".

Communication between two computers (shown in grey) connected through a third computer (shown in red) acting as a proxy. Note that Bob doesn’t know whom the information is going to, which is why proxies can be used to protect privacy.

In computer networks, a proxy server is a server (a computer system or an application) that acts as an intermediary for requests from clients seeking resources from other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource available from a different server and the proxy server evaluates the request as a way to simplify and control its complexity. Proxies were invented to add structure and encapsulation to distributed systems.[1]Today, most proxies are web proxies, facilitating access to content on the World Wide Web and providing anonymity.

Squid is a proxy server and web cache daemon. It has a wide variety of uses, from speeding up a web server by caching repeated requests; to caching web, DNS and other computer network lookups for a group of people sharing network resources; to aiding security by filtering traffic. Although primarily used for HTTP and FTP, Squid includes limited support for several other protocolsincluding TLS, SSL, Internet Gopher and HTTPS.

Squid was originally designed to run on Unix-like systems. A Windows port was maintained up to version 2.7, but more current versions are not being developed. Squid is free software released under the GNU General Public License.

Supported operating systems

Squid can run on the following operating systems:

  • AIX
  • BSDI
  • Digital Unix
  • FreeBSD
  • HP-UX
  • IRIX
  • Linux
  • Mac OS X
  • Microsoft Windows
  • NetBSD
  • NeXTStep
  • OpenBSD
  • OS/2 and eComStation
  • SCO OpenServer
  • Solaris
  • UnixWare

Content filtering,
URL Restriction,
Privillege Level of Internet Distribution,
Surfing Monitoring,
Reporting,
User,
Password,
Mac,
Active Directory,
MySql,
LDAP Integration,
MIME Protection,
Antivirus,
AntiSpy,
Control Panel,
Log Analysis,
Speedy Internet Connection,

Mailing Solution

Mailing Solution

 

Global Address Book,
My Sql,
Active Directory,
Ldap Integration,
Mail Achieving,
MailDir format,
IMAP,
POP3,
WEB MAIL,
Antispam,
Antivirus,
Attachment Rules,
Mail Analyser,
Control Panel,
Auto Responder,
Disclaimer,
Forwarders,
Catchall,
Grouping,
Unlimited User,
Unlimited Mail Rules,
Mail Backup,

Lot more

Linux Security

Linux Security

Linux Security Modules (LSM) is a framework that allows the Linux kernel to support a variety of computer security models while avoiding favoritism toward any single security implementation. The framework is licensed under the terms of the GNU General Public License and is standard part of the Linux kernel since Linux 2.6. AppArmor, SELinux, Smackand TOMOYO Linux are the currently accepted modules in the official kernel.

Design

LSM was designed to provide the specific needs of everything needed to successfully implement a mandatory access control module, while imposing the fewest possible changes to the Linux kernel. LSM avoids the approach of system call interposition as used in Systrace because it does not scale to multiprocessor kernels and is subject to TOCTTOU(race) attacks. Instead, LSM inserts “hooks” (upcalls to the module) at every point in the kernel where a user-level system call is about to result in access to an important internal kernel object such as inodes and task control blocks.

The project is narrowly scoped to solve the problem of access control to avoid imposing a large and complex change patch on the mainstream kernel. It is not intended as a general “hook” or “upcall” mechanism, nor does it support Operating system-level virtualization.

LSM’s access control goal is very closely related to the problem of system auditing, but is subtly different. Auditing requires that every attempt at access be recorded. LSM cannot deliver that, because it would require a great many more hooks, so as to detect cases where the kernel “short circuits” failing system calls and returns an error code before getting near significant objects.

The LSM design is described in the paper Linux Security Modules: General Security Support for the Linux Kernel presented at USENIX Security 2002. At the same conference was the paper Using CQUAL for Static Analysis of Authorization Hook Placement which studied automatic static analysis of the kernel code to verify that all of the necessary hooks have actually been inserted into the Linux kernel.

IT Monteur providing word class Linux Security Solution in Delhi India.

Clam Antivirus
Spam Assassin
Snort
Tripwire
Wireshark
Nessus
Nagious
Ntop
Nmap
Chkrootkit
Ethereal
Kismet
Iptables
Shorewall
IPCOP
SE Linux
PAM
TCP wrapper

Dedicated Linux Server Providers in India

Dedicated Linux Server Providers in India

Dedicated Linux Server Providers in India

 

Linux Dedicated Managed Server
Linux Dedicated Managed Server

 

IT Monteur provides support to meet your needs for designing, implementing and maintaining Linux systems, and with strong ties to the Linux open Source development community, IT Monteur has clearly recognized as the Linux server maintenance leader.

We are a One Stop Source for all Open Source Needs for any Organization. We provide cost-effective business ready solutions on services and subscription model using Linux and Open Source. Whether your servers are hosted with third parties or are located in your office, whether you require contracted unlimited support services or hourly support services, you’ll receive exceptional server support at all times.

When it comes to Linux servers, the situation is no different: simply put, the only certain way of maintaining uptime, preserving system security and ensuring service availability is to utilize a server management solution.  Our technical services are provided over a range of nix-based platforms, including most common variants of Linux (such as Redhat, CentOS, Fedora, Ubuntu and others), as well as FreeBSD.

We invite you to explore the specifics on the services we offer; for your convenience, they are summarized below. Nonetheless, should you have any question about any aspect of our products, support, services or maintenance, please feel free to contact us, and we will be more than happy to promptly answer your inquiry.

Linux Server Providers in India with Free Server Management

Linux Server Providers in India with Free Server Management

For more details on Linux Dedicated Server & Linux Server Management Services, Please contact us on

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