NETWORK STORAGE

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• NETWORK STORAGE

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NAS

• A network-attached storage (NAS) device is a
  server that is dedicated to nothing more than
  file sharing.
• NAS does not provide any of the activities that a
  server in a server-centric system typically
  provides, such as e-mail, authentication or file
  management.
• NAS allows more hard disk storage space to be
  added to a network that already utilizes servers
  without shutting them down for maintenance and
  upgrades.

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NAS

• With a NAS device, storage is not an integral
  part of the server.
• Instead, in this storage-centric design, the
  server still handles all of the processing of
  data but a NAS device delivers the data to the
  user.
• A NAS device does not need to be located within
  the server but can exist anywhere in a LAN and
  can be made up of multiple networked NAS devices.

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NAS

• NAS systems usually contain one or more hard
  disks, often arranged into logical, redundant
  storage containers or RAID arrays.
• The protocol used with NAS is a file based
  protocol such as NFS, Samba or Microsoft's Common
  Internet File System (CIFS).
• In reality, there is a miniature operating system
  on the device such as Celerra on EMC's devices or
  NetOS on NetApp NAS devices.

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NAS

• NAS devices become logical file system storage
  for a local area network.
• The performance of NAS devices depends heavily on
  cached memory (the equivalent of RAM) and network
  interface overhead (the speed of the router and
  network cards. The benefit is that the device can
  become a giant neighborhood hard drive for a
  whole building. The disadvantage is that any
  constrictions in the local network will slow down
  the resulting access time.)

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NAS

• NAS allows multiple server access through a
  file-based protocol. This allows administrators
  to implement simple and low cost load-balancing
  and fault-tolerant systems.
• For example
• Corporate e-mail system with multiple,
  load-balanced webmail servers
• Load-balanced web servers access the same
  contents from NAS storage

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Specs

• Intel P4 3.0Ghz
• 1GB ECC DDR RAM
• Microsoft Windows Storage Server 2003
• RAID 0, 1, 5 and JBOD
• 4 x 250GB Serial ATA-150 Hot Swap, Hard Disk
  Drive, 7200RPM, 8MB Cache
• Dual Auto Sensing Gigabit Ethernet Ports
  10/100/1000, RJ-45 Connector, with Teaming and
  Load Balancing

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NAS

• Simple right? Storing stuff is easy. Storing
  large amounts of stuff is easy. Backing it up
  sometimes is not.
• Often times, the backup solution is more
  expensive than the storage solution.

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NAS

• http//www1.us.dell.com/content/products/compare.a
  spx/tapeb_sing?cuscs04lensbsdtn1

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NAS backups

• Full file system image backup of all files within
  a NAS file system.
• How many tapes?
• How long?

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NAS backups

• Differential file system image backup of all
  files that have changed since the last full image
  backup.
• How much of savings is this?

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SANS

• A SAN, or Storage Area Network, is similar to
  NAS, but instead of being on the network, a SAN
  is generally on its OWN network.

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SANs

• SANS tend to be much larger scale than NAS
  solutions.
• Utilizing its own network to interconnect storage
  related resources without clogging a network.

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SANs

• SANs can provide many benefits. 
• Centralizing data storage operations and their
  management is certainly one of the chief reasons
  that SANs are being specified and deployed
  today. 
• Administrating all of the storage resources in
  high-growth and mission-critical environments can
  be daunting and very expensive.  SANs can
  dramatically reduce the management costs and
  complexity of these environments while providing
  significant technical advantages.

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SANs

• SANs can be based upon several different types of
  high-speed interfaces.  In fact, many SANs today
  use a combination of different interfaces. 
• Currently, Fibre Channel serves as the de facto
  standard being used in most SANs.  Fibre Channel
  is an industry-standard interconnect and
  high-performance serial I/O protocol that is
  media independent and supports simultaneous
  transfer of many different protocols. 

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SANs

• Additionally, SCSI interfaces are frequently used
  as sub-interfaces between internal components of
  SAN members, such as between raw storage disks
  and a RAID controller.
• SATA is actually becoming popular in this role as
  well.

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SANs

• Can hold a massive amount of drives
  (http//www1.us.dell.com/content/products/compare.
  aspx/sanet_fibre?cuscs555lensbiz )