Dell EMC D-PSC-MN-01 Exam Questions

In Dell EMC PowerScale F600 nodes, the Internal Dual SD Module (IDSDM) serves a specific role related to system configuration data. Understanding the function of the IDSDM is essential for maintaining system integrity and ensuring reliable operation.

Key Points:

Platform Serial Interface (PSI):

The PSI stores critical system configuration information such as node serial numbers, network configurations, cluster membership details, and hardware settings.

This data is vital for the node's identity and operation within the cluster.

Function of IDSDM:

The IDSDM acts as a secondary backup for the PSI information.

It provides an additional layer of protection by storing a redundant copy of the PSI data on removable SD cards.

This redundancy ensures that if the primary PSI data becomes corrupted or inaccessible, the system can recover using the backup from the IDSDM.

IDSDM Components:

The module contains two micro SD cards for redundancy.

Both SD cards store the same PSI information, enhancing reliability.

Why Option D is Correct:

Secondary Backup:

The primary copy of the PSI data resides on the node's motherboard.

The IDSDM serves as a backup location, making it the secondary backup for PSI information.

Why Other Options Are Incorrect:

Option A (Primary backup for PSI information):

Incorrect because the primary PSI data is on the motherboard, not on the IDSDM.

Option B (With two micro SD cards, it is a redundant backup for PSI information and temporary storage for FW upgrade binaries):

The IDSDM does not store firmware upgrade binaries; its sole purpose is to back up PSI data.

Option C (With one micro SD card...):

The IDSDM in F600 nodes uses two SD cards for redundancy but does not change its function based on the number of cards. It does not store firmware upgrade binaries.

Dell PowerScale Reference:

Dell EMC PowerScale F600 Technical Guide:

Section on System Components:

Explains the role of the IDSDM as a backup for PSI data.

Highlights the importance of PSI information for node operation.

Dell EMC PowerScale OneFS Administration Guide:

Chapter on System Configuration and Maintenance:

Details how the PSI data is stored, backed up, and recovered.

Emphasizes the function of the IDSDM in protecting configuration data.

Best Practices:

Regular Monitoring:

Check the health of the IDSDM during routine maintenance.

Secure Handling:

When servicing the IDSDM, ensure proper ESD precautions to prevent damage.

Documentation:

Keep records of any changes to the IDSDM or PSI data for troubleshooting purposes.

When a platform engineer removes the compute module from a Dell EMC PowerScale Gen 6 node and observes lit LEDs inside the removed node, this is a normal behavior due to the design of the node's power and indicator systems.

Reasons Why LEDs Remain Lit:

Residual Power:

The node's capacitors may hold residual power for a short time after shutdown, keeping LEDs lit temporarily.

Shared Power Supplies:

In Gen 6 nodes, power supplies may be shared between paired nodes, and some components might still receive power.

Recommended Response:

Proceed with the Procedure:

The lit LEDs are expected and do not indicate a fault.

The engineer should continue with the replacement procedure as per the guidelines.

Dell PowerScale Reference:

Dell EMC PowerScale Hardware Replacement Guide:

Section on Compute Module Replacement:

Notes that internal LEDs may remain lit after removal.

Confirms that this is normal and does not require additional action.

Safety Precautions:

Always ensure proper ESD protection when handling components.

Follow all recommended steps to safely replace hardware.

To safely power off a node in a Dell EMC PowerScale cluster, use the shutdown command with the appropriate options.

Command Details:

shutdown -p now:

shutdown: Initiates a system shutdown.

-p: Powers off the system after shutdown.

now: Executes the command immediately.

Why Other Options Are Incorrect:

Option A (isi status -q): Displays cluster status; doesn't control power.

Option B (isi status -h): Invalid option; isi status doesn't power off nodes.

Option D (shutdown -h now): Halts the system but may not power it off.

Dell PowerScale Reference:

Dell EMC PowerScale OneFS Administration Guide:

Shutting Down Nodes Section:

Recommends using shutdown -p now for powering off nodes.

Safety Precautions:

Advises to notify users and ensure no critical processes are running.

Best Practices:

Verify that the node is not hosting critical services before shutdown.

Inform cluster administrators of maintenance activities.

Adding F600 nodes to an existing cluster requires compatibility in back-end networking.

Key Considerations:

Back-End Networking:

F600 Nodes: Use Ethernet for internal communication.

Existing Nodes (X210 and H400): May be using InfiniBand.

Action Required:

Upgrade the cluster's back-end to Ethernet topology to accommodate F600 nodes.

Why Other Options Are Incorrect:

Option A: H400 nodes can coexist with F600 nodes if back-end networking is compatible.

Option B: F600 nodes do not use InfiniBand.

Option C: F600 nodes can coexist with X210 nodes with the appropriate back-end network.

Dell PowerScale Reference:

Dell EMC PowerScale Networking Guide:

Back-End Network Compatibility:

Discusses requirements for mixing node types.

Upgrading Back-End Network:

Provides steps for transitioning from InfiniBand to Ethernet.

Best Practices:

Plan the network upgrade carefully to minimize downtime.

Consult with Dell EMC support for guidance.

SolVe Desktop is a tool provided by Dell EMC that offers a centralized platform for accessing detailed, step-by-step procedures for servicing and maintaining Dell EMC equipment, including PowerScale systems.

Key Points:

Purpose of SolVe Desktop:

Acts as a comprehensive resource for service personnel.

Provides guided procedures for installation, maintenance, upgrades, and troubleshooting.

Features:

Interactive and customizable workflows.

Up-to-date documentation and best practices.

Access to knowledge base articles and technical advisories.

Benefits:

Ensures that engineers follow the correct procedures.

Reduces the risk of errors during service activities.

Enhances efficiency and effectiveness of maintenance tasks.

Dell PowerScale Reference:

SolVe Desktop User Guide:

Outlines the functionalities and how to use the tool effectively.

Emphasizes its role in providing access to step-by-step procedures.

Dell EMC Support Resources:

Encourages service personnel to utilize SolVe Desktop for accurate and approved methods.

Incorrect Options:

Option A (Gather logs from the cluster for analysis) is not the primary function of SolVe Desktop.

Option B (Perform pre-upgrade checks on the cluster) is a function of other tools like OneFS Upgrade Advisor.

Option D (Provide access to the latest OneFS codes and firmware upgrades) is handled through Dell EMC support portals.