EMC DMX LUN Presentation Procedure GUI

8/8/2019 EMC DMX LUN Presentation Procedure GUI

http://slidepdf.com/reader/full/emc-dmx-lun-presentation-procedure-gui 1/11

EMC DMX LUN Presentation Procedure This procedure provides the basic guidelines for creating a new LUN ona DMX array controller, presenting the new LUN to a host and (forSolaris) configuring the host to use the new LUN.LUN Presentation - DMX Required Steps

Typical steps for LUN creation on DMX are:• Device Creation/Configuration - This includes standard devices

and meta devices• Device Mapping - Presenting the device to a front end port.• Device Masking - Restricting access to the device/LUN to a

specific HBA (or set of HBAs).DMX Device Creation/Configuration

The EMC DMX line of arrays currently support SCSI-3 drives that areFC. Drive sizes currently on site include 300GB FC 10K, 146GB FC 15K,and 146GB FC 10K. Drive installation is performed by EMC. Physicaldrives in the DMX are split into slices/hypers. Currently, 5.66GB and13.62GB hyper sizes are the standard. Hypers typically have aprotection associated with them. Currently RAID1/Mirror andRAID5(7+1) are the two protection levels being used on DMX storage.

These hypers become the presented devices/LUNs. When disk drivesare installed, EMC works with the customer to develop a defaulthyper/slice layout for the disk drives.

Note: While it is possible to remove and create hypers/devicesin the DMX array for the purposes of resizing, moving or re-arranging the layout of the array, this type of activity is notrecommened. Performance and optimization layouts can beadversely affected by this type of operation. If this type of activity is required, it is best to work with EMC and have themperform any necessary work associated with the activity.

It is possible to merge hypers together to create a meta device for thepurpose of presenting units/LUNs larger than the standard 5.66GB or13.62GB LUNs. The current standard is to only create 4 or 8 device(call 4-way or 8-way) metas. Creating a meta with more than 8 hyperscan create a performance issue due to the way back-end disks areconnected to the DMX.

To create a meta device using EMC Control Center, use the followingsteps:

• Right-click on the DMX array and select Configure -> MetaDevice Configuration... (See Figure1 ).

https://hnwiki/twiki/pub/ITGStorageTeam/DMXLUNPresentation/Figure1-DMX.bmp




• The Meta Device Configuration screen appears (See Figure2 ).





•

• Expand the Unmapped Standard device folder in the left-handpane and select the devices to include in the meta (See Figure3 ).It is recommended that the devices selected be in numbericorder. This will assure that the load on the back-end is evenlydistributed. ( Note: Take care when selecting the devices toinclude in the meta so that a performance issue is not created ).





• In the right-hand pane, click on/highlight the Striped Metasfolder. ( Note: Concatenated Metas are considered obsolete and should never be used. There can be significant performanceissues for a LUN built with concatenated metas ).

• Click on the Create Meta button to create the meta device.• Expand the right-hand pane Striped Metas folder and locate the

new meta. The name/identifier for the meta will be the name/idof the first devices added as a member of the meta device.Verify that all devices have been included in the meta device tocreate.

• Click on the Continue button to review the proposed metadevice creation (See Figure4 ).





• Review the meta information and click on Execute and then on Yes to finish the meta device creation.

Device MappingDevice mapping is the process of presenting a device (either astandard hyper device or a meta device) to a front-end port on theDMX. At a minimum, a device is presented to two front-end ports. As astandard, the sum of the port numbers used to present the deviceshould total 17 (rule of 17). If a device is presented on port 11A-1, thenthe device would also be presented on port 6A-1.

To map a DMX device using EMC Control Center, use the following

steps:• Right-click on the DMX array and select Configuration -> SDR

Device Mapping... (See Figure5 ).





• A lock will be acquired on the array and a confirmation screenwill have to be acknowledged in order to proceed with the devicemapping. Click on the Yes button to continue.

• The SDR Device Mapping screen will be displayed (SeeFigure6 ).

• In the left-hand pane, expand the Unmapped Devices folderand select the device to map.• In the right-hand pane, expand the Host Directors and the

actual director to be used so that a port on the director can behighlighted/selected.

• Click on the Move button to map the device to the first port.Acknowledge the warning message by clicking on OK .

• To map the device to the other port, expand the Host Directorsfolder in the left-hand pane and the actual director that thedevice was mapped to.

• Continue to expand down the tree until the mapped device is

located (See Figure7 ).







• Once located, select/highlight the mapped device.• In the right-hand pane, expand the secondary port for the device

down to the port to present the device on.• Highlight/select the port and then click on the Copy button to

map the device to the second port.• Acknowledge the warning message by clicking on OK .• Click on Continue to call up the confirmation screen (See

Figure8 ).





• Review the settings and click on Execute to map the device tothe selected front-end ports. ( Note: Verify that the Address at Target value for the device is the same on each port. If they arenot, edit the entries to make them the same ).

• It will take several minutes to complete the mapping operation.Device MaskingDevice masking allows the access to a particular LUN on a DMX front-end port to be controlled down to the HBA level. This allows formultiple hosts to share front-end DMX ports without both hosts havingaccess to the same LUNs and creating a potential problem.

To set the masking on a device to allow a host access using EMCControl Center, perform the following steps:

• Expand the Hosts folder in EMC Control Center and continue toexpand the tree until an HBA WWN can be selected (SeeFigure9 ).





• Right-click on the WWN and select Masking -> ModifyMasking Configurations... .

• This will call up the Modify Masking Configurations screen(See Figure10 ).





• Working across the screen from left to right, top to bottom,select the array with the device to allow the host access to.

• Check the port/controller that the device was mapped to.• Change the Select Type of Device dropdown to All Devices

and then click on the Show Devices button.• Locate the device to mask in the bottom box and check the

device.• Click on the Grant button to give the HBA/host combination

access to the device.• Repeat this process for the other HBA (the currently uncheck one

in the upper left-hand box). Start by unchecking the current HBAand checking the other HBA.

• When all grants have been completed, click on the Continuebutton.

• The Modify Masking Configuration - Preview Changesscreen will be displayed (See Figure11 ).





• Review the changes to be made to the masking and click on theEdit Changes button to make corrections.

• To continue the masking operation, check the Activate the

VCMDB checkbox.• Click on the Execute button to complete the masking operation.

LUN Presentation - Host (Solaris) Required StepsOnce the LUN has been created and presented on the DMX array, thereare some configuration steps that are required on the host. Dependingon the version of Solaris and the HBA in use, those steps will vary buttypically come down to configuring the HBA, configuring the binding(persistent or dynamic) and editing /kernel/drv/sd.conf. After theseconfiguration steps are complete, a reboot of the host is necessary tosee the storage in most cases.

Documents

EMC DMX LUN Presentation Procedure GUI