Save Set Staging:

Save set staging is a process of transferring data from one storage medium to another. Staging reduces the time it takes to complete a backup by directing the initial backup to a high performance file type or adv_file device. The data can then be staged to a storage medium, freeing up the disk space. Any volume type, such as Default, Index Archive, or Default Clone, can be staged. Staging is particularly well suited for data that has been backed up on file type or adv_file devices. Staging allows the occupied disk space on file type or adv_file devices to be reclaimed so that the disk space can be used for other purposes. Use staging to move the data to more permanent storage, such as an optical or tape volume, or even another, lower-priority device. Staging also allows data to be moved off the device outside the backup period, ensuring that sufficient disk space is available for the next backup session. Additional licencing may be required.

You can create, edit, and delete staging policies as you can for other NetWorker resources. As part of the client setup, the use of a staging device can be selected for each pool (or set of pools) for backup, archive, and migration. The files are retained for the specified time in the disk staging pool before being moved to a tape device or optical disk. Any number of devices can be in the staging pool, and a save set can be staged as many times as required, for example to disk, to optical disk, to a local tape device, and to a remote tape device. Also, a volume can be staged to a second volume, and then that data on the second volume can be staged back to the first volume.

The staging process is driven by one of the following events:

- As part of an automatic process, such as keeping the save set for 30 days on the staging device before staging the data to the next device.

- As part of an event driven process, such as when available space in the staging pool drops below a set threshold. When this happens, the oldest save sets are moved first, until available space reaches the upper threshold that has been set.

- As part of an administrator initiated process, such as allowing the administrator to either reset the threshold and kick off staging or manually select save sets to stage.

When you enable a staging policy, the NetWorker server creates a clone of the save set you specify on a clone volume of the medium you specify. After the save set is staged, the save set is deleted from the filesystem to free the space.

The NetWorker server tracks the location of the save set in the media database. The retention policy for the save set does not change when the data is staged. If the file type volume is on a storage node that is running NetWorker software 6.1 or earlier, the tape is not automatically marked appendable after the staging operation.

There is available WWN decoder tool for EMC but I am going to discuss how to decode manually?
Each Symmetrix SAF port, RAF port, EF ficon port or DAF port (DMX only) has a unique worldwide name (WWN). The WWN is associated with the Tachyon chip on the director. It was intended to remain unique per director so that the director can be accessed on a storage area network. The Symmetrix SAF/RAF/DAF/EF WWN is dependent on the Symmetrix serial number, the director number, the processor letter, and the port on the processor. When the SAF/RAF/DAF is inserted into the Symmetrix, it discovers the Symmetrix serial number and slot number and the WWNs are set for the ports on the director.

Symm 4/4.8/5 (2-port or 4-port) Fibre Channel front directors, the WWN breakdown are as follows:

The director WWN (50060482B82F9654) can be broken down (in binary) as follows:

First 28 Bits (from the left, bits 63-36, binary) of WWN are assigned by the IEEE (5006048, the vendor ID for EMC Symmetrix)

5006048 2 B 8 2 F 9 6 5 4
0010 1011 1000 0010 1111 1001 0110 0101 0100

0 A E 0 B E 5 9 -----------------------> AE0BE59 hex = 182500953 Symm S/N

Bits 36 through 6 represent the Symmetrix serial number; the decode starts at bit 6 and works up to 36 to create the serial number. This is broken down as illustrated above.

The least signifigant 6 bits (bits 5 through 0) can be decoded to obtain the Symmetrix director number, processor and port. Bit 5 is used to designate the port on the processor (0 for A, 1 for B). Bit 4, known as the side bit, is used to designate the processor (0 for A, 1 for B). The least signifigant 4 bits, 3 through 0, represent the Symm slot number.


01 0100 = 14 hex -----> director 5b port A

In review, this WWN represents EMC Symmetrix serial number 182500953, director 5b port A

For Symm DMX product family (DMX-1/2/3), the WWN breakdown are as follows:

The director WWN (5006048ACCC86A32) can be broken down (in binary) as follows:

Again, like Symm 4/5, the first 28 bits (63-36) are assigned by the IEEE

5006048 A C C C 8 6 A 3 2

1010 1100 1100 1100 1000 0110 1010 0011 0010

B 3 3 2 1 A 8 ----------------------> B3321A8 hex = 187900328 Symm S/N

Bit 35 is now known as the 'Half' bit and is now used to decode which half the processor/port lie on the board.

Bits 34 through 6 represent the serial number; the decode starts at bit 6 and works up to bit 34 to create the serial number. This is broken down as illustrated above.

In conjunction with bit 35, the last 6 bits of the WWN represent the director number, processor and port. Bit 35, the 'Half' bit, represents either processor A and B, or C and D (0 for A and B, 1 for C and D). Bit 5 again represents the port on the processor (0 for A, 1 for B). Bit 4, the side bit, again represents the processor but with a slight change (if 0 then port A or C, if 1 then port B or D, depending on what the half bit is set to). The last 4 bits, 3 through 0, represent the Symm slot number.

1 11 0010 -------> half bit = 1 (either processor C or D), port bit = 1 (port B), side bit = 1 (because half = 1, looking at C and D processors only, side = 1 now means processor D)
0010 hex = 2 decimal (slot 2 or director 3)

In review, the WWN of 5006048ACCC86A32 represents EMC Symmetrix serial number 187900328, director 3d port B


Generally we never give thought about VCMDB database once we initialize first time. It does make sense when you messup or did some thing disaster. This database is most impppppportaaaaaaant for DMX. Once you loose this database means you can't get DMX configuration back at any cost. So, I am discussing different type of VCMDB on DMX.

We can now support up to 16,000/64000 addressable devices enginuity 5771 onward and therefore the Volume Control Manager Database needs to be physically larger. At 5670, as per EMC recommend CE's were encouraged to create 96 cylinder (minimum) VCMDB during new installs. This was to cater for future upgrades to 5671.

To summarize the VCMDB type applicable to DMX :

Type 3 - this can cater for 32 fibre or iSCSI initiators per port. Introduced with Enginuity 5669 and requires a 24 cylinder (minimum) VCMDB and Solutions Enabler v5.2.

Type 4 - this can cater for 64 fibre or 128 iSCSI initiators per port. Introduced with Enginuity 5670 and requires a 48 cylinder (minimum) VCMDB and Solutions Enabler v5.3.

• Type 5 - this can support 64 fibre or 128 iSCSI initiators per port AND cater for 16,000 devices. Introduced with Enginuity 5671 and requires a 96 cylinder (minimum) VCMDB and Solutions Enabler v6.0. (Note: without a type 5 96cyl VCMDB and SE 6.0 you will be restricted to 8192 logical volumes as in 5670).

Type 6 - this can support 128 fibre or 256 iSCSI initiators per port AND cater for 32,000 devices available on DMX-3 with Enginuity 5771 (at GA release). Currently the Type 6 database (at latest Enginuity 5771 with Solution Enabler 6.0 and above) will cater for 256 fibre or 512 iSCSI initiators and 64,000 logical devices.

What is requirement for Type 5:

The three requirements for a Type 5 VCM database on DMX (and support for up to 16,000 customer addressable volumes) is a correctly configured 96 cylinder VCMDB device, Enginuity 5671 and Solutions Enabler v6.0 or above. Note that the VCMBD “type” reflects the internal data structure of the Volume Control Manager Database. Therefore a 96 cylinder VCMDB size does NOT mean that you have a Type 5 VCMDB.

Note:
• At 5670 with a 48 cylinder VCMDB it is still type 4.
• At 5670 with a 96 cylinder VCMDB it is still type 4.
• At 5670 with a 96 cylinder VCMDB and SE 6.0 it is still type 4 - do not try to convert the database using the SYMCLI (EMC do not support more than 8192 logical volumes at 5670).
• At 5671 with a 48 cylinder VCMDB and SE 6.0 it is still type 4 - the VCMDB is NOT physically large enough.
• At 5671 with a 96 cylinder VCMDB and SE 5.5 it is still type 4 - the VCMDB is large enough but SE 5.5 does not support the Type 5 database.
• At 5671 with a 96 cylinder VCMDB and SE 6.0 it is a type 5 database - if you have run the “symmaskdb convert -vcm_type 5” command. Be aware that if you convert from a lower type database to a higher type, any hosts running a Solutions Enabler version that does not support the higher VCMDB type will NOT be able to access the "new" database.
• At 5771 (DMX-3) the VCMDB data now resides in the SFS volumes. At 5771 the VCMDB should be configured the SAME size as a standard FBA gatekeeper (this can be 3 cylinders due to the 64KB track size but 6 cylinder, as recommended in some guides, is also perfectly acceptable) but it must still be assigned the VCM fibre gatekeeper status. Note that the VCMDB "gatekeeper" on DMX-3 is no longer shown as "write disabled" (it is now a "gatekeeper" rather than a physical volume used for physical storage - the Volume Control Manager data is protected and stored on the internal SFS volumes).
• Note that Enginuity 5771 will ONLY support a Type 6 VCM database (again the data is resident on the SFS volumes). This re-location of the physical database to the SFS volumes caters for the increased host connectivity AND the increase in logical volumes supported with DMX-3.

I am going to discuss about TimeFinder BCV Split operation where Host running on Oracle Database. This split operation is different from normal BCV split operation. There are differences in command as well. Thats reason I am putting steps for this:

The following steps describes splitting BCV devices that hold a database supporting a host running an Oracle database. In this case, the BCV split operation is in an environment without PowerPath or ECA. The split operation described here suspends writes to a database momentarily while an instant split occurs. After an establish operation and the standard device and BCV mirrors are synchronized, the BCV device becomes a mirror copy of the standard device. You can split the paired devices to where each holds separate valid copies of the data, but will no longer remain synchronized to changes when they occur.

The Oracle database is all held on standard and BCV devices assigned to one Oracle device group.

1) Check device status on the database BCVs
To view and check status of the database BCV pairs, use the following form:

symmir –g DgName query

Check the output to ensure all BCV devices listed in the group are in the synchronized state

2) Check and set the user account

For SYMCLI to access a specified database, set the SYMCLI_RDB_CONNECT environment variable to the username and password of the system administrator’s account. The export action sets this variable to a username of system and a password of manager, allowing a local connection as follows:

export SYMCLI_RDF_CONNECT=system/manager

The ORACLE_HOME command specifies the location of the Oracle binaries and the ORACLE_SID command specifies the database instance name as follows:

export ORACLE_HOME=/disks/symapidvt/oraclhome/api179
export ORACLE_sid=api179


You can test basic database connectivity with the symrdb command as follows:

symrdb list –type oracle

3) Backup the database

For safety, perform a database hot backup. For example:

symioctl begin backup –type oracle –nop


4) Freeze the database
For safety, perform a freeze on the database I/O. For example:

symioctl freeze –type oracle –nop

This command suspends writes to the Oracle database.

5) Split all BCV devices in the group
To split all the BCV devices from the standard devices in the database device group, enter:

symmir –g oraclegrp split –instant -noprompt

Make sure the split operation completes on all BCVs in the database device group.

6) Thaw the database to resume I/O
To allow writes to the database to resume for normal operation, enter:

symioctl thaw –type oracle –nop

7) End the backup
To terminate the hot backup mode, enter the following command:

symioctl end backup –type oracle –nop

Vendor Worldwide Names WWN :


Twenty-four of the sixty-four bit •World Wide Name• must be unique for every vendor. A partial listing of those vendors most familiar to EMC with regard to Symmetrix Fibre Channel connectivity.

If decoding a HBA WWN, then issue an 8f, command to view the WWN in the FA login table. Bytes 1-3 of the World Wide Names contain the unique vender codes. Note that if there is a switch connected between the FA and the host bus adapter, then the name and fabric servers of the switch will login to the FA. These WWNs can be decoded in the same way as the HBA WWNs.

In the following example the unique vendor code is 060B00, this indicates that the HBA attached was supplied by Hewlett Packard.

UTILITY 8F -- SCSI Adapter utility : TIME: APR/23/01 01:23:30
------------------------------------

HARD LOOP ID : 000 (ALPA=EF) LINK STATE : ONLINE: LOOP
CHIP TYPE/REV: 00/00 Q RECS TOTAL: 3449 CREDIT: 0 RCV BUFF SZ: 2048

IF FLAGS : 01/ TAGD/NO LINK/NO SYNC/NO WIDE/NO NEGO/NO SOFT/NO ENVT/NO CYLN
IF FLAGS1: 08/NO PBAY/NO H300/NO RORD/ CMSN/NO QERR/NO DQRS/NO DULT/NO SUNP
IF FLAGS2: 00/NO SMNS/NO DFDC/NO DMNQ/NO NFNG/NO ABSY/NO SQNT/NO NRSB/NO SVAS
IF FLAGS3: 00/NO SCI3/NO ..../NO ..../NO ..../NO ..../NO ..../NO ..../NO ....

FC FLAGS : 57/ ARRY/ VOLS/ HDAD/NO HDNP/ GTLO/NO PTOP/ WWN /NO VSA
FC FLAGS1: 00/NO VCM /NO CLS2/NO OVMS/NO ..../NO ..../NO ..../NO ..../NO ....
FC FLAGS2: 00/NO ..../NO ..../NO ..../NO ..../NO ..../NO ..../NO ..../NO ....
FC FLAGS3: 00/NO ..../NO ..../NO ..../NO ..../NO ..../NO ..../NO ..../NO ....

HOST SID PORT NAME (WWN) NODE NAME RCV BUF CREDIT CLASS
-----------------------------------------------------------------------------
000001 50060B0000014932 50060B0000014933 992 EE 4 3
PRLI REQ: IFN RXD
DONE.

The following are common HBA vendor codes:

Refer to the open systems host matrix if you need to know whether these HBAs are supported for specific hosts.

00-00-D1 (hex) ADAPTEC INCORPORATED
0000D1 (base 16) ADAPTEC INCORPORATED

00-30-D3 (hex) Agilent Technologies
0030D3 (base 16) Agilent Technologies

00-60-69 (hex) BROCADE COMMUNICATIONS SYSTEMS
006069 (base 16) BROCADE COMMUNICATIONS SYSTEMS

00-02-A5 (hex) Compaq Computer Corporation
0002A5 (base 16) Compaq Computer Corporation

00-60-48 (hex) EMC CORPORATION
006048 (base 16) EMC CORPORATION

00-00-C9 (hex) EMULEX CORPORATION
0000C9 (base 16) EMULEX CORPORATION

00-E0-24 (hex) GADZOOX NETWORKS
00E024 (base 16) GADZOOX NETWORKS

00-60-B0 (hex) HEWLETT-PACKARD CO.
0060B0 (base 16) HEWLETT-PACKARD CO.

00-50-76 (hex) IBM
005076 (base 16) IBM

00-E0-69 (hex) JAYCOR NETWORKS, INC.
00E069 (base 16) JAYCOR NETWORKS, INC.

08-00-88 (hex) MCDATA CORPORATION
080088 (base 16) MCDATA CORPORATION

08-00-0E (hex) NCR CORPORATION
08000E (base 16) NCR CORPORATION

00-E0-8B (hex) QLOGIC CORP.
00E08B (base 16) QLOGIC CORP.

00-00-6B (hex) SILICON GRAPHICS INC./MIPS
00006B (base 16) SILICON GRAPHICS INC./MIPS
,
00-10-9B (hex) VIXEL CORPORATION
00109B (base 16) VIXEL CORPORATION
This information will help you to identify the vendor of particularar HBA's WWN.

Brocade Switches:
How to merge two switches with different active zone sets."

Merging Two B-series Directors and/or Switches with Different Active Zoning Configurations
Before Beginning The following procedure is disruptive to fabric traffic.:
--It will require disabling the switch and the removal of the effective zoning configurations at one step. Removing this configuration will stop the data flow. Since this step in the procedure takes only a few moments to complete, data should resume as soon as the new configuration is activated.
To evaluate the impact on an OS platforms and applications, please refer to the ESN Topology Guide for OS platform timeout recommendations as well as the actual configuration files of the servers to identify their current timeout settings.

Supported Director and Switch Types
The following information on fabric merging applies to the following EMC Director and Switch types:
ED-12000B
DS-32B2
DS-16B2
DS-16B
DS-8B
NOTE: Also applies to similar OEM version of these switch types. See ESM for latest switch firmware qualification prior to merging non-EMC Directors and/or Switches into an EMC SAN.

Host Requirements:
A host computer with a FTP service is required.

Merging

1. Log into the first switch via telnet or WebTools
a. Known as “swo1” for this example
b. For DS-16Bs, DS-8Bs, and comparable switch models running firmware 2.5.0d and above, default access zoning must be set to “ALLACCESS”
NOTE: This is an offline command that will interrupt data flow.
1. Issue switchdisable command
2. Issue configure command
3. Enter “y” when prompted for “Zoning Operation parameters”
4. Enter “1” when prompted for “Default Access”
5. Enter “n” for all other parameters
6. Issue switchenable command
2. Upload the first switch (or one switch of a multi-switch fabric) configuration to a host using FTP
a. Use configupload command or use WebTools
b. Name the file “sw01_config.txt”
1. All zoning and configuration data for this switch will be located in this file.
3. Log into the second switch via telnet or WebTools
a. Known as “sw02” for this example
b. For DS-16Bs, DS-8Bs, and comparable switch models running firmware 2.5.0d and above, default access zoning must be set to “ALLACCESS”
NOTE: This is an offline command that will interrupt data flow.
1. Issue switchdisable command
2. Issue configure command
3. Enter “y” when prompted for “Zoning Operation parameters”
4. Enter “1” when prompted for “Default Access”
5. Enter “n” for all other parameters
6. Issue switchenable command
4. Upload the switch configuration to a host using FTP
a. Use configupload command or use WebTools
b. Name the file “sw02_config.txt”
1. All zoning and configuration data for this switch will be located in this file.
5. Open in a text editor (i.e. Microsoft Word, VI, emacs, etc) for both “sw01_config.txt” and “sw02_config.txt” files
a. The uploaded configuration contains a list of switches in the fabric, list of ISLs, list of ports, name server data, and zoning information.
b. For the purposes of merging, one need only be concerned with the zoning section of the uploaded configuration, which may be found at the end of the file. It contains zones, aliases, and defined and effective configurations.

Example sw01_config.txt Zoning Section
[Zoning]
cfg.cfg_1:zone_1
zone.zone_1:10:00:00:08:00:00:00:01
alias.HBA1:10:00:00:08:00:00:00:01
enable:cfg_1
Example sw02_config.txt Zoning Section
[Zoning]
cfg.cfg_2:zone_2
zone.zone_2:10:00:00:00:09:00:00:02
alias.HBA2:10:00:00:00:09:00:00:02
enable:cfg_2


6. Make a copy of “sw01_config.txt” and rename the copy as “configmerge.txt”
7. Copy aliases from “sw02_config.txt”
a. Highlight and copy the alias data
8. Paste aliases from “sw02_config.txt” to “configmerge.txt”
a. Paste under existing alias data in “configmerge.txt”
9. Copy zones from “sw02_config.txt”
a. Highlight and copy the zone data
10. Paste zones from “sw02_config.txt” to “configmerge.txt”
a. Paste under existing zone data in “configmerge.txt”
11. Copy zone names from “cfg.cfg” line of “[Zoning]” section from “sw02_config.txt” to “configmerge.txt”
a. Copy zone name(s) to “cfg.cfg” line after existing zones separating each zone with a semicolon
b. The last zone name will not be followed by a semicolon

Example Configmerge.txt Zoning Section After Paste from sw02_config.txt
[Zoning]
cfg.cfg_1:zone_1;zone_2
zone.zone_1:10:00:00:08:00:00:00:01
zone.zone_2:10:00:00:00:09:00:00:02
alias.HBA1:10:00:00:08:00:00:00:01
alias.HBA2:10:00:00:00:09:00:00:02
enable:cfg_1


NOTE: Areas highlighted in red above illustrate the additions from “sw02_config.txt”
12. Save changes to “configmerge.txt”
13. Download “configmerge.txt” to sw01
a. Use configdownload command or use WebTools
1. If using configdownload command, the switch must be manually disabled before downloading commences. Use the switchdisable command. After completion, the switch must be manually enabled. Use the switchenable command.
2. Using WebTools automatically disables and re-enables the switch.
b. After downloading, the newly merged configuration is automatically the effective configuration because it is already specified in the “[Zoning]” section as the enabled configuration.
14. Issue cfgsave command on sw01
a. Saves the configuration to flash
15. Issue cfgshow command to see defined and effective zoning configurations
Example Output of cfgshow Command on sw01 After Configmerge.txt is Downloaded

Defined configuration:
cfg: cfg_1 zone_1; zone_2
zone: zone_1 10:00:00:08:00:00:00:01
zone: zone_2 10:00:00:00:09:00:00:02
alias: HBA1 10:00:00:08:00:00:00:01
alias: HBA2 10:00:00:00:09:00:00:02
Effective configuration:
cfg: cfg_1
zone: zone_1 Protocol:ALL 10:00:00:08:00:00:00:01
zone: zone_2 Protocol:ALL 10:00:00:00:09:00:00:02


16. On sw02, issue the following commands to remove both defined and effective zoning configurations
a. cfgdisable
b. cfgclear
c. cfgsave
17. Issue cfgshow command to see defined and effective zoning configurations
Example Output of “cfgshow” Command on Second Switch After Removing the Configuration
Defined configuration:
no configuration defined
Effective configuration:
no configuration in effect
18. Connect the switches via a fiber optic cable to the ports chosen to be E_ports.
a. sw02 will inherit the zoning data from sw01 when they exchange fabric parameters.
NOTE: Be sure to check that both switches have unique Domain IDs. Be sure to check the fabric parameters such as EDTOV, RATOV, Data Field Size, Core Switch PID are identical.
19. Issue cfgshow command on second switch to see defined and effective zoning configurations.
Example Output of cfgshow Command on sw02 After Fabric Merge

Defined configuration:
cfg: cfg_1 zone_1; zone_2
zone: zone_1 10:00:00:08:00:00:00:01
zone: zone_2 10:00:00:00:09:00:00:02
alias: HBA1 10:00:00:08:00:00:00:01
alias: HBA2 10:00:00:00:09:00:00:02
Effective configuration:
cfg: cfg_1
zone: zone_1 Protocol:ALL 10:00:00:08:00:00:00:01
zone: zone_2 Protocol:ALL 10:00:00:00:09:00:00:02


NOTE: Zoning configurations on both switches are now identical.
20. Issue switchshow and fabricshow commands to verify a successful fabric merge

Hope this info will help you to replace a switch in your enviornment or merge.

There are different type of SAN like IP SAN, NAS over SAN etc... We will discuss about Fibre Channel SAN. It gives you more option in order to manage and minimize downtime means reducing company cost.

In general if you think storage environments, physical interfaces to storage consisted of parallel SCSI channels supporting a small number of SCSI devices. With Fibre Channel, the technology provides a means to implement robust storage area networks that may consist of 100’s of devices. Fibre Channel storage area networks yield a capability that supports high bandwidth storage traffic on the order of 100 MB/s, and enhancements to the Fibre Channel standard will support even higher bandwidth in the near future.

Depending on the implementation, several different components can be used to build a Fibre Channel storage area network. The Fibre Channel SAN consists of components such as storage subsystems, storage devices, and server systems that are attached to a Fibre Channel network using Fibre Channel adapters. Fibre Channel networks in turn may be composed of many different types of interconnect entities. Examples of interconnect entities are switches, hubs, and bridges.

There are various type of SAN implementation so lets discuss little bit about physical view and logical view of SAN.

The physical view allows the physical components of a SAN to be identified and the associated
physical topology between them to be understood. Similarly, the logical view allows the relationships and associations between SAN entities to be identified and understood.

Physical View

From a physical standpoint, a SAN environment typically consists of four major classes of components. These four classes are:
· End-user platforms such as desktops and/or thin clients;
· Server systems;
· Storage devices and storage subsystems;
· Interconnect entities.
Typically, network facilities based on traditional LAN and WAN technology provide connectivity between end-user platforms and server system components. However in some cases, end-user platforms may be attached to the Fibre Channel network and may access storage devices directly. Server system components in a SAN environment can exist independently or as a cluster. As processing requirements continue to increase, computing clusters are becoming more prevalent.

We are using new term cluster. this itself is big topic to cover but we will have brief idea about cluster. A cluster is defined as a group of independent computers managed as a single system for higher availability, easier manageability, and greater scalability. Server system components are
interconnected using specialized cluster interconnects or open clustering technologies such as the Fibre Channel - Virtual Interface mapping. Storage subsystems are connected to server systems, to end–user platforms, and to each other using the facilities of a Fibre Channel network. The Fibre Channel network is made up of various interconnect entities that may include switches, hubs, and bridges.





Logical View

From a logical perspective, a SAN environment consists of SAN components and resources, as well as their relationships, dependencies and other associations. Relationships, dependencies, and associations between SAN components are not necessarily constrained by physical connectivity. For example, a SAN relationship may be established between a client and a
group of storage devices that are not physically co-located. Logical relationships play a key role in the management of SAN environments. Some key relationships in the SAN environment are identified below:


· Storage subsystems and interconnect entities;
· Between storage subsystems;
· Server systems and storage subsystems (including adapters);
· Server systems and end-user components;
· Storage and end-user components;
· Between server systems.


As a specific example, one type of relationship is the concept of a logical entity group. In this case, server system components and storage components are logically classified as connected components because they are both attached to the Fibre Channel network. A logical entity group forms a private virtual network or zone within the SAN environment with a specific set of
connected entities as members. Communication within each zone is restricted to its members.
In another example, where a Fibre Channel network is implemented using a switched fabric, the Fibre Channel network may further still be broken down into logically independent sections called sub-fabrics for each possible combination of data rate and class of service. Sub-fabrics are again divided into regions and extended-regions based on compatible service parameters.
Regions and extended regions can also be divided into partitions called zones for administrative purposes.

About Me

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Sr. Solutions Architect; Expertise: - Cloud Design & Architect - Data Center Consolidation - DC/Storage Virtualization - Technology Refresh - Data Migration - SAN Refresh - Data Center Architecture More info:- diwakar@emcstorageinfo.com
Blog Disclaimer: “The opinions expressed here are my personal opinions. Content published here is not read or approved in advance by EMC and does not necessarily reflect the views and opinions of EMC.”