Most Recent Dell EMC D-RP-OE-A-24 Exam Questions & Answers

1.The production host writes data to the production volumes, but is first intercepted by the splitter. The splitter sends the write data to the RPA.

2.Immediately upon receipt of the write data, the local RPA returns an acknowledgement (ACK) to the splitter.

3.The splitter then writes the data to the production storage volume.

4.The storage system returns an ACK to the splitter upon successfully writing the data to storage.

5.The splitter sends an ACK to the host that the write has been completed successfully

RecoverPoint Write Phase:

In the RecoverPoint replication process, the write splitter plays a crucial role in intercepting writes from the host and forwarding them to both the production storage and the RecoverPoint appliances (RPAs).

Write Splitter Functionality:

The write splitter intercepts write I/O requests from the host and splits the I/O to both the production LUN and the RPAs. This ensures that the data is written to both the primary storage and replicated copies.

Acknowledgement Process:

During the write phase, the write splitter must ensure that the data is successfully written to the production LUN before acknowledging the write request back to the host.

This is because the primary concern is ensuring data integrity and confirming that the data is safely stored in the production environment before any replication considerations.

Detailed Workflow:

Step 1: Host issues a write request.

Step 2: The write splitter intercepts the write request.

Step 3: The write splitter forwards the write to the production LUN and the RPAs.

Step 4: The production LUN processes the write and sends an acknowledgement back to the write splitter.

Step 5: Upon receiving the acknowledgement from the production LUN, the write splitter then sends an acknowledgement back to the host.

According to the Dell RecoverPoint for Virtual Machines 6.0.1 vSphere HTML5 Plugin Administrator's Guide:

'The write splitter sends an acknowledgement to the host after it receives an acknowledgement from the production LUN' (vrpa.pdf, p.17).

'Ensuring that the write is committed to the production LUN before sending an acknowledgement to the host guarantees data integrity and consistency' (vrpa.pdf, p.18).

RecoverPoint and VMAX Connectivity:

A physical RecoverPoint cluster connected to a VMAX array uses Fibre Channel connections for communication. Each RPA typically has two Fibre Channel ports.

WWPN (World Wide Port Name):

WWPNs are unique identifiers assigned to each port in a Fibre Channel network, including both RecoverPoint and VMAX ports.

Minimum Number of WWPNs:

For a single RecoverPoint appliance (RPA), the minimum number of ports includes:

2 RecoverPoint Ports (RP Ports): Each RPA usually has at least two Fibre Channel ports for redundancy.

1 Front-End Adapter (FA) Port: The VMAX array has at least one FA port connected to the RecoverPoint system.

Diagnostic Tests:

When running SAN diagnostics from the boxmgmt menu, the test will show the WWPNs of all connected ports, including both the RPA ports and the VMAX FA ports.

From the Dell RecoverPoint for Virtual Machines 6.0.1 documentation and standard SAN configuration principles:

'Each RecoverPoint appliance typically connects to the storage array using two Fibre Channel ports' (general SAN configuration best practices).

'The VMAX array will have at least one FA port connected to the RecoverPoint system for data transfer and replication purposes.'

Therefore, when running SAN diagnostics from the boxmgmt menu, the minimum number of WWPNs that can be seen in the storage ports section of the diagnostic test is 3 (2 RPA ports + 1 FA port).

A MetroPoint Consistency Group is a special type of Consistency Group in Dell RecoverPoint that is designed for environments where high availability and disaster recovery are critical. It includes:

Active Production Copies: These are the primary copies that are actively used in the production environment.

Standby Production Copies: These copies are on standby and can be activated in case the active production copies fail or need to be taken offline for maintenance.

The MetroPoint Consistency Group allows for continuous data protection and availability across multiple sites, combining the benefits of VPLEX Metro with the third-site replication provided by RecoverPoint1.