SAN & NAS

1. SAN & NAS Group - 05

2. Group Partners K.P.K.N. SomarathnaET/10/7956 K.K.S.P. Perera ET/10/7922 T.D.M.B.K. Ranasinghe ET/10/7923 H.M.G.R. Bandara ET/10/7935 E.M.P.M. EkanayakeET/10/7929

3. Network-attached storage (NAS) Network-attached storage (NAS) is file-level computer data storage connected to a computer network providing data access to a heterogeneous group of clients. Heterogeneous computing refers to systems that use more than one kind of processor.

4. Network-attached storage (NAS) • 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.

5. Network-attached storage (NAS) • As of 2010 NAS devices are gaining popularity, as a convenient method of sharing files among multiple computers. • 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..

6. Network-attached storage (NAS) • One or more disk 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.

7. Network-attached storage (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

8. Network-attached storage (NAS) 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 disks, often arranged into logical, redundant storage containers or RAID.

9. Why NAS is Benefit than File server…. compared to file servers, • faster data access. • NAS systems strive for reliable operation and easy administration. • simple configuration • Very Efficiency. • Very Flexible.

10. Why NAS is Benefit than File server…. • NAS Remove 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, or AFP. • 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.

11. Network-attached storage (NAS) • NAS systems are networked appliances which contain one or more hard drives, often arranged into logical, redundant storage containers or RAID. • RAID (originally redundant array of inexpensive disks; now commonly redundant array of independent disks) is a data storage virtualization technology that combines multiple disk drive components into a logical unit for the purposes of data redundancy or performance improvement.

12. Network-attached storage (NAS) The NAS devices can be classified into three types. • Computer based NAS • Embedded system based NAS • ASIC based NAS

13. Network-attached storage (NAS) 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.

14. Network-attached storage (NAS) 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.

15. Network-attached storage (NAS) 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.

16. Network-attached storage (NAS) clustered NAS • A clustered NAS is a NAS that is using a distributed file system running simultaneously on multiple servers. • The key difference between a clustered and traditional NAS is the ability to distribute data and metadata across the cluster nodes or storage devices. • Clustered NAS, like a traditional one, still provides unified access to the files from any of the cluster nodes, unrelated to the actual location of the data.

17. Protocol used in NAS….. Andrew File System (AFS) -  is a distributed file system which uses a set of trusted servers to present a homogeneous, location-transparent file name space to all the client workstations. Apple Filing Protocol (AFP) - is a proprietary network protocol that offers file services for Mac OS X and original Mac OS. In Mac OS X, AFP is one of several file services supported, with others including Server Message Block (SMB), Network File System (NFS), File Transfer Protocol (FTP)

18. Protocol used in NAS….. Server Message Block (CIFS, former SAMBA)- one version of which was also known as Common Internet File System (CIFS),  operates as an application-layer network protocol mainly used for providing shared access to files, printers, serial ports, and miscellaneous communications between nodes on a network. File Transfer Protocol (FTP)- s a standard network protocol used to transfer computer files from one host to another host over a TCP-based network, such as the Internet.

19. Protocol used in NAS….. Hypertext Transfer Protocol (HTTP)- The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems. Network File System (NFS, a UNIX protocol)- Network File System (NFS) is a distributed file system protocol originally developed by Sun Microsystems in 1984, allowing a user on a client computer to access files over a network much like local storage is accessed.

20. Protocol used in NAS….. Rsync- rsync is a utility software and network protocol for Unix-like systems (with a port to Microsoft Windows) that synchronizes files and directories from one location to another while minimizing data transfer by using delta encoding when appropriate. SSH file transfer protocol (SFTP)- In computing, the SSH File Transfer Protocol (also Secure File Transfer Protocol, or SFTP) is a network protocol that provides file access, file transfer, and file managementfunctionalities over any reliable data stream. Universal Plug and Play (UPnP)-Universal Plug and Play (UPnP) is a set of networking protocols that permits networked devices.

21. In the Beginning Servers were built with Limited Storage Expansion Easy to use No extra cost All files are on the same drive  But growing networks needs more Space 

22. JBOD (Now we have much space) Just a Bunch Of Disks (JBOD) More Storage Not much more cost Not shared between servers Expandable Storage Capacity Ooopz But we need more space, and we also needs to share files between each other

23. What is SAN • Dedicated network that provides access to consolidated, block level data storage • SANs are primarily used to enhance storage devices • Accessible to servers so that the devices appear like locally attached devices to the operating system

24. Building blocks of a SAN Server Drive Enclosures (Most of the times a DAS) Controllers Switch Host Bus Adaptors SAN Management Software SFPs & cables

25. Shared SAN Shared Storage Area Network (Shared SAN) Ideal enterprise-class solution for customers with low-to-medium performance requirements Support for block-access storage protocols only Pay-as-you-grow, start with and pay for the resources required for today and add more capacity if and when you need it No need to worry about over-purchasing or overgrowing your storage environment in a few months or years

26. Dedicated SAN Dedicated Storage Area Network (dSAN) Ideal Enterprise-class solution for customers with high-performance and highly secure storage needs Support for file & block-access storage protocols (CIFS/NFS/Fibre Channel) Snapshots and clones enable easy data backup and local replication dSAN to dSAN replication between Rackspace Data Centers is available to address regional disasters and outages or other business-impacting events Allows Rackspace DC to Rackspace DC array-based replication between dSAN arrays using asynchronous RecoverPoint Appliance

27. SAN Infrastructure SANs often use a Fibre Channel FabricTopology - an infrastructure specially designed to handle storage communications. A fabric is similar in concept to a network segment in a local area network. A typical Fibre Channel SAN fabric is made up of a number of Fibre Channel switches. SAN equipment vendors also offer some form of Fibre Channel Routing solution These bring substantial scalability benefits to the SAN architecture by allowing data to cross between different fabrics without merging them.

28. SAN Types ATA over Ethernet (AoE), mapping of ATA over Ethernet Fibre Channel Protocol (FCP), the most prominent one, is a mapping of SCSI over Fibre Channel Fibre Channel over Ethernet (FCoE) ESCON over Fibre Channel (FICON), used by mainframe computers HyperSCSI, mapping of SCSI over Ethernet iFCP or SANoIPmapping of FCP over IP iSCSI, mapping of SCSI over TCP/IP iSCSI Extensions for RDMA (iSER), mapping of iSCSI over InfiniBand

29. iSCSI Internet Small Computer System Interface IP based storage networking protocol for linking data storage facilities The protocol allows clients (called initiators) to send SCSI commands (CDBs) to SCSI storage devices (targets) on remote servers It carries SCSI commands over IP networks iSCSI can be used to transmit data over local area networks (LANs), wide area networks (WANs), or the Internet Enables location-independent data storage and retrieval

30. iFCP Internet Fibre Channel Protocol It is a gateway-to-gateway network protocol standard The iFCP protocol enables the implementation of fibre channel functionality over an IP network Congestion control, error detection and recovery are provided through the use of TCP Permits fibre channel storage devices and host adapters to be attached to an IP-based fabric using transparent gateways.

31. Fibre Channel Topologies

32. Storage virtualization Storage virtualization is the process of abstracting logical storage from physical storage. The physical storage resources are aggregated into storage pools, from which the logical storage is created. It presents to the user a logical space for data storage and transparently handles the process of mapping it to the physical location, a concept called location transparency. This is implemented in modern disk arrays, often using vendor proprietary solutions. The goal of storage virtualization is to group multiple disk arrays from different vendors, scattered over a network, into a single storage device.

35. SANs in media and entertainment • High Availability - A high-availability (HA) clustered architecture allows organizations to maximize data availability and operational efficiency. • Low Latency - optimized for long, sequential files with minimal network overhead, achieving up to 90% of underlying hardware speeds. • Massive Scalability - supports tens of billions of files in a single file system together with hundreds of clients • Global Name Support - All clients share a single global namespace. Administrators can expand, move, re-balance and reconfigure • storage without affecting how users view and access it while incurring no downtime.

36. SAN Storage QoS (Quality of Service) Key factors that affect Storage Area Network QoS(Quality of Service) are: • Bandwidth – The rate of data throughput available on the system. • Latency– The time delay for a read/write operation to execute. • Queue depth – The number of outstanding operations waiting to execute to the underlying disks (Traditional or SSD). • QoS can be impacted in a SAN storage system by unexpected increase in data traffic (usage spike) from one network user that can cause performance to decrease for other users on the 

37. Compatibility issues • One of the early problems with Fiber Channel SANs was that the switches and other hardware from different manufacturers were not compatible. •  The basic storage protocols FCP were always quite standard, some of the higher-level functions did not interoperate well. •  many host operating systems would react badly to other operating systems sharing the same fabric. • Many solutions were pushed to the market before standards were finalized and vendors have since innovated around the standards

38. Benefits of SAN Availability:SAN storage is in general more reliable than DAS attached disk. The cost of an hour of application downtime varies from company to company but can exceed millions in some cases. Disk utilization:The space that is unutilized is wasted until it is needed. In SANs, that space can be "assigned" to any server that needs more storage, thus deferring new storage purchases. Using DAS, I find that a 40% utilization rate is high whereas in a SAN, you can get to the ultimate 80/20 (used/unused) ratio without a problem. Management:Using DAS you need to manually install new disks to add storage. In a SAN you can remotely assign it to a server. No downtime and perhaps not even a reboot is required if the OS can handle it. You can manage ALL your storage GLOBALLY from a single console. Backup:Using snapshots and data replication can save your backside when disasters happen and using a SAN for centralizing data backup can improve recovery time dramatically while reducing overall costs by sharing tape resources and eliminating backup windows.

39. Disadvantages of SAN SANs Fiber channel technology tends to be pricier and maintenance requires a higher degree of skill. There are a few SAN product vendors due to its very high price and very few mega enterprises need SAN set up.

40. Ethernet Comparison Storage Server • NAS was designed before the emergence of SAN as a solution to the limitations of Direct Attached Storage (DAS). • DAS was simply an extension to an existing server and is not necessarily networked

41. Storage mode • SAN supports block access to data(as a locally attached storage). • Can be accessed by using client’s own file system. • Visible in disk and volume management utilities (along with client's local disks), and available to be formatted with a file system and mounted. • NAS is basically remote file serving. • Operating as a server with its own file system. • Appears as a file server to client’s OS (normally a browser is used for accessing).

42. A SAN solution can be loosely described as a network of storage disks. • A SAN connects multiple server systems to a centralized pool of disk storage. • By treating all the storages as a single resource, disk maintenance and backups are easier to schedule and control. • Provides high-speed disk access capabilities. • The SAN network allows data transfers among server systems and subsystems at the same speeds, as if the subsystems were directly attached to the server systems. • SAN over IP (IPSAN) enables data transfers via IP over fast Gigabit Ethernet (locally) or via the Internet (remotely).

43. The NAS head (also called a NAS Gateway) represents the part of the NAS solution required for the clients to connect to the IO subsystem. • The clients have to access the IO space via the NAS head which serves as the actual control function of the system. • Different types of communication protocols are used in NAS heads for different manufacturers (UNIX, Windows, Apple Mac, OES, Novell NetWare).

44. The goal of both SAN and NAS to solution the various computers in a network, to share a more centralized collection of storage devices via a network connection through the LAN.

45. Infrastructure and protocols • SAN uses FibreChannel, iSCSI, ATA over Ethernet (AoE) and HyperSCSI for managing the connections. • Uses FibreChannel encapsulated SCSI setups for storage. • NAS utilizes TCP/IP based networks such as Ethernet, FDDI, or ATM. • NAS uses file-based protocols such as NFS (Network File System), SMB/CIFS (Server Message Block/Common Internet File System), AFP (Apple Filing Protocol), or NCP (NetWare Core Protocol).

46. More differences

47. SAN-NAS hybrid • SAN and NAS can be combined to take the benefits of both systems. • Offering both file-level protocols and block-level protocols (SAN) from the same system.