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Start of the FRAME locator

Frame header (includes destination ID and source id, 24 bytes/6 words)

Data Payload (encapsulate SCSI instruction can be 0-2112 bytes in length)

CRC (error checking, 4 bytes)

END of Frame (1 byte)

Start of the Frame locator

Frame header (includes destination id and source id, 24 bytes/6 words)

Data Payload (encapsulate SCSI instruction can be 0-2112 bytes in length)

CRC (error checking, 4 bytes)

End of Frame (1 byte)

Virtualization is LOGICAL representation of physical devices. It is the technique of managing and PRESENTING storage devices and resources functionally, regardless of their physical layout or location. Virtualization is the pooling of physical storage from multiple network storage devices into what APPEARS to be a single storage device that is managed from a central console. Storage virtualization is commonly used in a storage area network (SAN). The management of storage devices can be tedious and time-consuming. Storage virtualization helps the storage ADMINISTRATOR perform the tasks of backup, archiving, and recovery more easily, and in less time, by disguising the actual complexity of the SAN.

Virtualization is logical representation of physical devices. It is the technique of managing and presenting storage devices and resources functionally, regardless of their physical layout or location. Virtualization is the pooling of physical storage from multiple network storage devices into what appears to be a single storage device that is managed from a central console. Storage virtualization is commonly used in a storage area network (SAN). The management of storage devices can be tedious and time-consuming. Storage virtualization helps the storage administrator perform the tasks of backup, archiving, and recovery more easily, and in less time, by disguising the actual complexity of the SAN.

HA High Availability is a technology to achieve failover with very less latency. Its a PRACTICAL REQUIREMENT of data centers these days when CUSTOMERS expect the servers to be running 24 hours on all 7 days around the whole 365 days a year - usually referred as 24x7x365. So to achieve this, a redundant infrastructure is created to MAKE sure if one database server or if one app server fails there is a replica Database or Appserver ready to take-over the operations. END customer never experiences any outage when there is a HA network infrastructure.

HA High Availability is a technology to achieve failover with very less latency. Its a practical requirement of data centers these days when customers expect the servers to be running 24 hours on all 7 days around the whole 365 days a year - usually referred as 24x7x365. So to achieve this, a redundant infrastructure is created to make sure if one database server or if one app server fails there is a replica Database or Appserver ready to take-over the operations. End customer never experiences any outage when there is a HA network infrastructure.

There are many types of TAPE media available to back up the data some of them are:

• DLT: digital linear tape - technology for tape backup/archive of networks and servers; DLT technology addresses midrange to high-end tape backup requirements.
• LTO: linear tape open; a new standard tape format developed by HP, IBM, and Seagate.
• AIT: advanced INTELLIGENT tape; a helical SCAN technology developed by Sony for tape backup/archive of networks and servers, specifically addressing midrange to high-end backup requirements.

There are many types of tape media available to back up the data some of them are:

No, SINCE R0 is not redundant ARRAY, failure of any disks results in failure of the entire array so we cannot REBUILD the hot SPARE for the R0 array.

No, since R0 is not redundant array, failure of any disks results in failure of the entire array so we cannot rebuild the hot spare for the R0 array.

QAS: Quick arbitration and SELECTION

Domain Validation

CRC: CYCLIC redundancy CHECK

QAS: Quick arbitration and selection

Domain Validation

CRC: Cyclic redundancy check

There are STATES of RAID ARRAYS that represent the status of the RAID arrays which are GIVEN below:

• Online
• Degraded
• Rebuilding
• Failed

There are states of RAID arrays that represent the status of the RAID arrays which are given below:

You NEED to have at least 3 disk drives to create R5.

You need to have at least 3 disk drives to create R5.

dmesg

dmesg

• Core-edge
• Full-Mesh
• Partial-Mesh
• CASCADE

SAN can be connected in 3 types which are mentioned below:

• Point to Point TOPOLOGY
• FC ARBITRATED LOOP ( FC :FIBRE Channel )
• Switched Fabric

SAN can be connected in 3 types which are mentioned below:

Array is a GROUP of Independent physical disks to CONFIGURE any Volumes or RAID volumes.

Array is a group of Independent physical disks to configure any Volumes or RAID volumes.

In some scenarios you are supposed to install Operating System on the DRIVES CONNECTED thru SCSI HBA or SCSI RAID CONTROLLERS, but most of the OS will not be UPDATED with drivers for those controllers, that time you need to supply drivers externally, if you are installing windows, you need to press F6 during the installation of OS and provide the DRIVER disk or CD which came along with HBA.

If you are installing Linux you need to type "linux dd" for installing any driver.

In some scenarios you are supposed to install Operating System on the drives connected thru SCSI HBA or SCSI RAID Controllers, but most of the OS will not be updated with drivers for those controllers, that time you need to supply drivers externally, if you are installing windows, you need to press F6 during the installation of OS and provide the driver disk or CD which came along with HBA.

If you are installing Linux you need to type "linux dd" for installing any driver.

There are 16 different ID’s which can be assigned to SCSI device 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8.

Highest priority of SCSI is ID 7 and lowest ID is 8.

There are 16 different ID’s which can be assigned to SCSI device 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8.

Highest priority of SCSI is ID 7 and lowest ID is 8.

GENERALLY the default ID for SCSI HBA is 7.

• SCSI- SMALL Computer System Interface
• HBA - Host BUS Adaptor

Generally the default ID for SCSI HBA is 7.

There are MANY MANAGEMENT SOFTWARE’s used for MANAGING SAN's to name a few

• Santricity
• IBM Tivoli Storage Manager.
• CA Unicenter.
• Veritas Volumemanger.

There are many management software’s used for managing SAN's to name a few

Each component has its own CRITICALITY with respect to BUSINESS NEEDS of a company.

Each component has its own criticality with respect to business needs of a company.

These are Data TRANSFER media they will sit on PCI slots of SERVER; you can CONFIGURE Arrays and volumes on it.

These are Data transfer media they will sit on PCI slots of Server; you can configure Arrays and volumes on it.

Fabric SWITCH: It's a device which interconnects multiple network devices .There are switches starting from 16 port to 32 ports which CONNECT 16 or 32 machine NODES etc. vendors who manufacture these kind of switches are BROCADE, McData.

Fabric Switch: It's a device which interconnects multiple network devices .There are switches starting from 16 port to 32 ports which connect 16 or 32 machine nodes etc. vendors who manufacture these kind of switches are Brocade, McData.

If we consider any small business FOLLOWING are essentials components of SAN

• Fabric SWITCH
• FC CONTROLLERS
• JBOD's

If we consider any small business following are essentials components of SAN

The basic difference between SAN and NAS, SAN is Fabric based and NAS is Ethernet based.

SAN - Storage AREA Network

It accesses data on block LEVEL and produces SPACE to host in form of DISK.

NAS - Network attached Storage

It accesses data on file level and produces space to host in form of shared network folder.

The basic difference between SAN and NAS, SAN is Fabric based and NAS is Ethernet based.

SAN - Storage Area Network

It accesses data on block level and produces space to host in form of disk.

NAS - Network attached Storage

It accesses data on file level and produces space to host in form of shared network folder.

• Massively extended scalability
• Greatly enhanced device connectivity
• Storage consolidation
• LAN-free backup
• Server-less (active-fabric) backup
• Server clustering
• Heterogeneous data sharing
• Disaster recovery - REMOTE mirroring
• While answering people do NOT portray clearly what they MEAN & what ADVANTAGES each of them have, which are cost effective & which are to be USED for the client's requirements.

HOST bus adapters (HBAS) are needed to CONNECT the server (host) to the STORAGE.

Host bus adapters (HBAs) are needed to connect the server (host) to the storage.

RAID: “Redundant Array of Inexpensive Disks”

• Fault-tolerant grouping of disks that server sees as a single disk VOLUME
• Combination of parity-checking, mirroring, striping
• Self-contained, manageable unit of storage

JBOD: “Just a Bunch of Disks”

• DRIVES independently attached to the I/O CHANNEL
• SCALABLE, but requires server to manage multiple volumes
• Do not provide protection in case of drive failure

RAID: “Redundant Array of Inexpensive Disks”

JBOD: “Just a Bunch of Disks”

“Just a BUNCH of DISKS”

It is a collection of disks that SHARE a common CONNECTION to the server, but don’t include the mirroring, striping, or parity facilities that RAID systems do, but these capabilities are available with host-based software.

“Just a Bunch of Disks”

It is a collection of disks that share a common connection to the server, but don’t include the mirroring, striping, or parity facilities that RAID systems do, but these capabilities are available with host-based software.

RAID 0+1 (Mirrored Stripped)

In this RAID level all the data is saved on stripped volumes which are in turn mirrored, so any disk FAILURE SAVES the data loss but it makes whole stripe unavailable. The key difference from RAID 1+0 is that RAID 0+1 creates a second striped set to mirror a primary striped set. The array continues to operate with one or more DRIVES failed in the same mirror set, but if drives fail on both sides of the mirror the data on the RAID system is LOST. In this RAID level if one disk is failed full mirror is marked as inactive and data is saved only one stripped volume.

RAID 1+0 (Stripped Mirrored)

In this RAID level all the data is saved on mirrored volumes which are in turn stripped, so any disk failure saves data loss. The key difference from RAID 0+1 is that RAID 1+0 creates a striped set from a series of mirrored drives. In a failed disk situation RAID 1+0 performs better because all the remaining disks continue to be USED. The array can sustain multiple drive losses so long as no mirror loses both its drives.

This RAID level is most preferred for high performance and high data protection because rebuilding of RAID 1+0 is less time consuming in comparison to RAID 0+1.

RAID 0+1 (Mirrored Stripped)

In this RAID level all the data is saved on stripped volumes which are in turn mirrored, so any disk failure saves the data loss but it makes whole stripe unavailable. The key difference from RAID 1+0 is that RAID 0+1 creates a second striped set to mirror a primary striped set. The array continues to operate with one or more drives failed in the same mirror set, but if drives fail on both sides of the mirror the data on the RAID system is lost. In this RAID level if one disk is failed full mirror is marked as inactive and data is saved only one stripped volume.

RAID 1+0 (Stripped Mirrored)

In this RAID level all the data is saved on mirrored volumes which are in turn stripped, so any disk failure saves data loss. The key difference from RAID 0+1 is that RAID 1+0 creates a striped set from a series of mirrored drives. In a failed disk situation RAID 1+0 performs better because all the remaining disks continue to be used. The array can sustain multiple drive losses so long as no mirror loses both its drives.

This RAID level is most preferred for high performance and high data protection because rebuilding of RAID 1+0 is less time consuming in comparison to RAID 0+1.

LAN hardware and operating systems are geared to user TRAFFIC, and LANs are tuned for a fast user response to messaging requests.

With a SAN, the storage units can be SECURED separately from the servers and totally apart from the user network enhancing storage access in data BLOCKS (BULK data TRANSFERS), advantageous for server-less backups.

LAN hardware and operating systems are geared to user traffic, and LANs are tuned for a fast user response to messaging requests.

With a SAN, the storage units can be secured separately from the servers and totally apart from the user network enhancing storage access in data blocks (bulk data transfers), advantageous for server-less backups.

Point-to-point, ARBITRATED LOOP, and SWITCHED FABRIC TOPOLOGIES.

Point-to-point, arbitrated loop, and switched fabric topologies.

For environments consisting of HIGH-end SERVERS that require high bandwidth or data center environments with business-critical data, FIBRE Channel is a better fit than iSCSI. For environments consisting of many midrange or low-end servers, an IP SAN solution often delivers the most appropriate price/performance.

For environments consisting of high-end servers that require high bandwidth or data center environments with business-critical data, Fibre Channel is a better fit than iSCSI. For environments consisting of many midrange or low-end servers, an IP SAN solution often delivers the most appropriate price/performance.

FIBRE Channel and iSCSI each have a distinct place in the IT infrastructure as SAN alternatives to DAS. Fibre Channel generally provides high PERFORMANCE and high availability for business-critical applications, USUALLY in the corporate data center. In contrast, iSCSI is generally used to provide SANS for business applications in smaller regional or departmental data centers.

Fibre Channel and iSCSI each have a distinct place in the IT infrastructure as SAN alternatives to DAS. Fibre Channel generally provides high performance and high availability for business-critical applications, usually in the corporate data center. In contrast, iSCSI is generally used to provide SANs for business applications in smaller regional or departmental data centers.

Benefits include twice the performance with little or no price increase, investment protection with backward compatibility to 2 GB, higher reliability due to fewer SAN COMPONENTS (SWITCH and HBA ports) required, and the ability to replicate, back up, and restore data more quickly. 4 GB Fibre CHANNEL systems are ideally suited for APPLICATIONS that need to quickly TRANSFER large amounts of data such as remote replication across a SAN, streaming video on demand, modeling and rendering, and large databases. 4 GB technology is shipping today.

Benefits include twice the performance with little or no price increase, investment protection with backward compatibility to 2 GB, higher reliability due to fewer SAN components (switch and HBA ports) required, and the ability to replicate, back up, and restore data more quickly. 4 GB Fibre Channel systems are ideally suited for applications that need to quickly transfer large amounts of data such as remote replication across a SAN, streaming video on demand, modeling and rendering, and large databases. 4 GB technology is shipping today.

Fibre CHANNEL is a well-established, widely deployed technology with a proven track record and a very LARGE installed base, particularly in high-performance, business-critical data center environments. Fibre Channel SANs continue to grow and will be enhanced for a long time to come. The reduced costs of Fibre Channel components, the availability of SAN KITS, and the next generation of Fibre Channel (4 GB) are helping to fuel that growth. In addition, the Fibre Channel roadmap includes PLANS to double performance every three years.

Fibre Channel is a well-established, widely deployed technology with a proven track record and a very large installed base, particularly in high-performance, business-critical data center environments. Fibre Channel SANs continue to grow and will be enhanced for a long time to come. The reduced costs of Fibre Channel components, the availability of SAN kits, and the next generation of Fibre Channel (4 GB) are helping to fuel that growth. In addition, the Fibre Channel roadmap includes plans to double performance every three years.

Development started in 1988, ANSI standard approval occurred in 1994, and large DEPLOYMENTS BEGAN in 1998. Fibre Channel is a mature, safe, and widely deployed solution for high-speed (1 GB, 2 GB, 4 GB) communications and is the FOUNDATION for the majority of SAN installations throughout the WORLD.

Development started in 1988, ANSI standard approval occurred in 1994, and large deployments began in 1998. Fibre Channel is a mature, safe, and widely deployed solution for high-speed (1 GB, 2 GB, 4 GB) communications and is the foundation for the majority of SAN installations throughout the world.

The increased performance of Fibre Channel enables a highly effective backup and recovery approach, including LAN-free and server-free backup models. The result is a faster, more SCALABLE, and more reliable backup and recovery solution. By PROVIDING flexible connectivity options and resource sharing, Fibre Channel SANs also greatly reduce the NUMBER of physical devices and disparate systems that must be purchased and managed, which can dramatically LOWER capital expenditures. Heterogeneous SAN management provides a single point of control for all devices on the SAN, lowering COSTS and freeing personnel to do other tasks.

The increased performance of Fibre Channel enables a highly effective backup and recovery approach, including LAN-free and server-free backup models. The result is a faster, more scalable, and more reliable backup and recovery solution. By providing flexible connectivity options and resource sharing, Fibre Channel SANs also greatly reduce the number of physical devices and disparate systems that must be purchased and managed, which can dramatically lower capital expenditures. Heterogeneous SAN management provides a single point of control for all devices on the SAN, lowering costs and freeing personnel to do other tasks.

TYPICALLY, fibre CHANNEL SANs are most suitable for large data centers running business-critical data, as well as applications that require high-bandwidth performance such as medical imaging, streaming MEDIA, and large DATABASES. Fibre Channel SAN solutions can easily scale to meet the most demanding performance and AVAILABILITY requirements.

Typically, fibre channel SANs are most suitable for large data centers running business-critical data, as well as applications that require high-bandwidth performance such as medical imaging, streaming media, and large databases. Fibre Channel SAN solutions can easily scale to meet the most demanding performance and availability requirements.

Fibre Channel SANs are the DE facto standard for STORAGE networking in the corporate data CENTER because they provide EXCEPTIONAL reliability, scalability, consolidation, and performance. Fibre Channel SANs provide significant advantages over direct-attached storage through improved storage UTILIZATION, higher data availability, reduced management costs, and highly scalable capacity and performance.

Fibre Channel SANs are the de facto standard for storage networking in the corporate data center because they provide exceptional reliability, scalability, consolidation, and performance. Fibre Channel SANs provide significant advantages over direct-attached storage through improved storage utilization, higher data availability, reduced management costs, and highly scalable capacity and performance.