EMC Updated D-VPX-OE-A-24 Exam Questions and Answers by gwen

For migrating a Microsoft SQL Server and its native EMC VNX LUNs behind a VPLEX Local cluster with the ability to expand storage volumes in the future, the recommended geometry during encapsulation is 1:1 mapping.This approach allows for each storage volume to be directly mapped to a virtual volume, preserving the data in its current state and simplifying future expansions1.

1:1 Mapping: This geometry ensures that each back-end storage volume is encapsulated into a corresponding virtual volume in VPLEX.It maintains a direct relationship between the physical LUN and the virtual volume1.

Future Expansion: With 1:1 mapping, expanding a virtual volume is straightforward because it involves expanding the underlying storage volume on the array and then resizing the corresponding virtual volume in VPLEX1.

Encapsulation Process: During encapsulation, the storage administrator can prepare many tasks ahead of time, such as host zoning to VPLEX FE ports, host registration of initiators in VPLEX, and LUN masking/zoning to the VPLEX BE Ports.The cutover process then becomes a quick procedure to switch the volumes1.

EZ Provisioning Wizard: After claiming and encapsulating the LUNs, the administrator can create a 1:1 mapping of Storage volume to virtual volume with the EZ Provisioning Wizard, which is a quick process and helps preserve the data in its current state1.

Simplifying Management: By using 1:1 mapping, the storage administrator simplifies the management of storage volumes and ensures that the SQL Server can be easily expanded to accommodate future application growth1.

By selecting 1:1 mapping during the encapsulation process, the storage administrator ensures that the system is prepared for future growth and that storage volumes can be expanded without complications.

A supported geometry for a VPLEX device is RAID-C, which stands for RAID Concatenation. RAID-C is a VPLEX-specific RAID configuration that concatenates multiple extents or devices to create a larger virtual volume.

RAID Concatenation (RAID-C): RAID-C is a VPLEX geometry that allows for the concatenation of multiple storage extents or devices.This configuration is used to create larger virtual volumes by combining smaller ones1.

Use of RAID-C: RAID-C is typically used when there is a need to expand storage capacity without the requirement for additional redundancy.It is a simple way to increase the size of a virtual volume by adding more storage to it1.

Advantages: The advantage of using RAID-C is that it allows for flexibility in storage provisioning and can be easily expanded as storage needs grow.It also enables the use of storage from different arrays1.

VPLEX Device Configuration: In the context of VPLEX, a device refers to a logical unit that can be presented to hosts.By using RAID-C geometry, VPLEX can present larger logical units that span across multiple physical storage arrays1.

Supported Geometries: VPLEX supports various RAID geometries, including RAID-0, RAID-1, and RAID-C, each serving different purposes and providing different levels of performance and protection1.

By utilizing RAID-C geometry, VPLEX administrators can manage storage more effectively, ensuring that they can meet the capacity requirements of their applications and services.

Before a host can detect the virtual volumes presented by VPLEX, it is necessary for the host to initiate a bus-scan of the Host Bus Adapters (HBAs). This process allows the host to recognize new storage devices that have been presented to it, such as the virtual volumes from VPLEX.

Here’s a detailed explanation:

Host Bus Adapters (HBAs): HBAs are the hardware interfaces that connect a host system to a network or storage device. In the context of VPLEX, they connect the host to the VPLEX storage system.

Bus-Scan: A bus-scan is a command that can be issued from the host to scan the storage network for any changes, such as newly added storage volumes. This is typically done using operating system-specific commands or utilities.

Virtual Volumes Detection: Once the bus-scan is complete, the host’s operating system can detect the virtual volumes presented by VPLEX and make them available for use by applications and services running on the host.

No RAID Requirement: The detection of virtual volumes does not require RAID configuration to be enabled for the volumes themselves, as this is managed within the VPLEX system.

No Reboot Necessary: It is not necessary to reboot the host to detect virtual volumes. A bus-scan can be performed while the system is running without requiring a restart.

No Wizard Required: The EZ Provisioning wizard is a tool used within the VPLEX system for provisioning storage, but it is not required to be run on the host for virtual volume detection.

By initiating a bus-scan of the HBAs, the host can detect and utilize the virtual volumes presented by VPLEX, allowing for flexible and dynamic storage management.