Due to increased amount of data in enterprise business,storage has become most important to any business in the recent history.Cloud storage becomes popular due to its increased productivity and low cost in the market.In this post we can see some major storage concepts.
DAS - Directly attached storage
SAN - Storage Area Network
NAS - Network attached storage
In DAS, storage system(hard disk) is directly attached to server.This approach is seen in traditional desktop computers where hard disk have a dedicated connection to system motherboard.
Data is transferred through SCSI commands.Standard Buses used between the hard disk and computer are
SCSI, ATA and SATA
NAS is a file based storage, where storage resources are directly attached to LAN. NAS provides storage space to clients by sharing protocols such as NFS(Network File System) and CIFS(Common Internet File Sharing).
NFS - Commonly used sharing protocol in UNIX and Linux platform.
CIFS - Commonly used sharing protocol in Windows system.
NAS uses various network protocols such as HTTP,FTP and TCP/IP.
In NAS device, processor runs its own embedded operating system to provide access to shared storage.
SAN is a block based storage.It provides block based access to data through SCSI, FCAL/FCP and iSCSI protocols.
Block is a sequence of bits or bytes having nominal length.
Sharing of data is difficult in SAN.
In each server hardware HBA adapter is installed to provide block transfer of data through Fabric channel switches.
LUN - A disk provided by the SAN to client system that looks like locally attached storage.
Target - A system (SAN) that offers disk(LUN) to another client system to access storage.
Initiator - Client system that import the LUN provided by the SAN.Appropriate initiator software must be installed to access LUN.
Fabric - It is a collection of fiber channel switches ,that inter connects target and initiators.
There are three types of storage
DAS - Directly attached storage
SAN - Storage Area Network
NAS - Network attached storage
DAS
In DAS, storage system(hard disk) is directly attached to server.This approach is seen in traditional desktop computers where hard disk have a dedicated connection to system motherboard.
Data is transferred through SCSI commands.Standard Buses used between the hard disk and computer are
SCSI, ATA and SATA
NAS
NAS is a file based storage, where storage resources are directly attached to LAN. NAS provides storage space to clients by sharing protocols such as NFS(Network File System) and CIFS(Common Internet File Sharing).
NFS - Commonly used sharing protocol in UNIX and Linux platform.
CIFS - Commonly used sharing protocol in Windows system.
NAS uses various network protocols such as HTTP,FTP and TCP/IP.
In NAS device, processor runs its own embedded operating system to provide access to shared storage.
SAN
SAN is a block based storage.It provides block based access to data through SCSI, FCAL/FCP and iSCSI protocols.
Block is a sequence of bits or bytes having nominal length.
Sharing of data is difficult in SAN.
In each server hardware HBA adapter is installed to provide block transfer of data through Fabric channel switches.
LUN - A disk provided by the SAN to client system that looks like locally attached storage.
Target - A system (SAN) that offers disk(LUN) to another client system to access storage.
Initiator - Client system that import the LUN provided by the SAN.Appropriate initiator software must be installed to access LUN.
Fabric - It is a collection of fiber channel switches ,that inter connects target and initiators.