NS0-093 NetApp Accredited Hardware Support Engineer Questions and Answers

 Upgrade Considerations for Disk and CPU Utilization:

During an ONTAP upgrade, it is critical to ensure the system has sufficient resources to handle the upgrade process without impacting normal operations.

 Recommended Threshold:

NetApp recommends that both disk and CPU utilization should be below 70% before initiating an upgrade. This ensures that there is enough headroom for the upgrade operations and avoids performance degradation.

 Steps to Verify Utilization:

Use the system node show -fields cpu command to check CPU usage.

Use the storage aggregate show -fields used command to check aggregate disk utilization.

 NetApp Reference Documentation:

"ONTAP Upgrade and Maintenance Guide" specifies the 70% threshold for disk and CPU usage during upgrade planning.

The "ONTAP Performance Management Guide" provides methods for monitoring system resource utilization.

If the root volume runs out of space, it can cause operational issues and require recovery.

The root volume must always have sufficient space for system logs, configuration files, and core dumps.

1. Root Volume Ran Out of Space:

When a mainboard is replaced, the system configuration stored in the root volume may need to be restored or recovered.

2. Mainboard Was Replaced Following an NMI Panic:

C. Root volume migrate was performed:

Root volume migration is a normal operation and does not typically cause the need for root volume recovery.

D. The cluster configuration is out of sync on the volume:

While this can cause configuration issues, it does not directly lead to root volume recovery.

Why Other Options Are Incorrect:

"ONTAP Root Volume Management Guide" explains scenarios leading to root volume issues and recovery procedures.

References:

To view information about installed Field Replaceable Units (FRUs) using the Service Processor, the following commands are used:

What it does:Displays a list of all installed FRUs, such as disks, power supplies, and fans.

Example Usage:

1. system fru listsystem fru list

What it does:Provides detailed information about specific FRUs, including serial numbers, statuses, and hardware details.

2. system fru showsystem fru show

C. system sensors show:

This command displays sensor data (e.g., temperature, voltage) but does not list FRUs.

D. system power status:

This command shows power supply status but does not provide FRU details.

Why Other Options Are Incorrect:

"Service Processor Commands Guide" from NetApp provides a comprehensive overview of system fru list and system fru show.

References:

When a node fails to boot and loads the previous version of ONTAP, it usually indicates that the primary boot location is incorrect. To resolve this:

Enter the LOADER Prompt:

Interrupt the boot process to access the LOADER prompt.

Set the Primary Kernel URL:

Use the following command:

Steps to Boot the Correct ONTAP Version:setenv GX_PRIMARY_KERNEL_URL

Boot the Node:

Run the boot command to load the correct version.

B. From the loader prompt of nodeA1, run boot_backup:

Booting the backup image may result in an outdated version of ONTAP, not the desired version.

C. From the clustershell of the partner, run system node image modify:

Modifications to the ONTAP image must be done from the LOADER prompt, not the clustershell.

D. From the clustershell of nodeA1, run system node image modify:

NodeA1 cannot load ONTAP, so this command cannot be run.

Why Other Options Are Incorrect:

"ONTAP System Boot Guide" explains how to resolve boot issues using the LOADER prompt.

NetApp documentation on environment variables includes the use of GX_PRIMARY_KERNEL_URL.

References:

To ensure that POST (Power-On Self-Test) runs on boot, the setenv POST=true command is used at the LOADER prompt. This command enables the system to perform POST diagnostics before proceeding with the boot process.

POST Purpose: POST checks system hardware components (such as memory, disk, and controllers) for faults before loading the ONTAP kernel.

How to Use:

At the LOADER prompt, type:

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setenv POST=true

Save the configuration and reboot the system.

B. bye:

This command restarts the system but does not ensure that POST runs on boot.

C. boot_diag:

This command boots the system into diagnostic mode but is not directly related to enabling POST on boot.

D. boot_ontap:

This command boots ONTAP but skips POST if it is not explicitly enabled.

Why Other Options Are Incorrect:

NetApp "ONTAP System Boot and Recovery Guide" describes setenv POST=true for enabling POST diagnostics.

References:

To confirm the successful completion of an ONTAP upgrade, the cluster image show-update-progress command provides the necessary details.

Command:

Key Command:cluster image show-update-progress

Displays the status of the cluster upgrade, including which nodes have successfully upgraded and whether the process has completed.

A. system controller sp upgrade show:

This command displays information about SP (Service Processor) firmware upgrades, not ONTAP upgrades.

C. job show –jobtype upgrade:

While this command shows upgrade jobs, it does not confirm the completion of the cluster-wide ONTAP upgrade.

D. system node upgrade-revert upgrade-task –node <nodename> –version <ontap Version>:

This command reverts an upgrade task, not confirms completion.

Why Other Options Are Incorrect:

NetApp "ONTAP Upgrade Guide" specifies the cluster image show-update-progress command as the primary method to verify upgrade completion.

References:

On a FAS9000 system running ONTAP 9.12.1, the kernel core file is stored on the root aggregate. This is the default location where ONTAP writes kernel core files for system-level failures.

The root aggregate is the aggregate that contains the root volume for a given node in the cluster. This aggregate is used for critical system files and logs, including kernel core files.

When a kernel panic or other critical failure occurs, the core dump is written to the root aggregate for later analysis by NetApp Support.

Key Details:

A. on the partner root aggregate: The partner root aggregate is not used for storing core files unless explicitly configured (which is not the default behavior).

C. on the mailbox disk: The mailbox disk is used for cluster quorum and configuration information, not for storing core files.

D. on the boot device: The boot device contains ONTAP software and boot files but does not store kernel core dumps.

"ONTAP System Administration Guide" specifies that core files are stored on the root aggregate.

NetApp’s "Troubleshooting and Diagnostics Guide" confirms the default behavior for kernel core file storage.

Why Other Options Are Incorrect:References:

To reset environment variables to factory settings, the set-defaults command is used. This command clears all customizations and restores the environment variables to their default values.

Command Syntax:At the LOADER prompt, type:

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set-defaults

Effect:This command resets all environment variables (e.g., boot arguments, diagnostic settings) to their original factory defaults.

B. unsetenv all:

This command clears all environment variables, but it does not restore them to factory defaults.

C. setenv factory:

This is not a valid command in NetApp systems.

D. wipeconfig:

This command is used to clear configuration and logs but does not reset environment variables.

Why Other Options Are Incorrect:

NetApp "System Configuration Guide" confirms the use of set-defaults for restoring environment variables to factory settings.

References:

The identifier 1.2.3.L1 follows the NetApp disk naming convention, which specifies the location of the drive in the system. Here is the breakdown of the identifier:

1: This indicates the stack ID or loop ID. It represents the stack number in the disk shelf configuration.

2: This indicates the shelf ID. In this case, the drive is located in shelf 2.

3: This indicates the bay ID or slot number within the shelf. The drive is in bay 3.

L1: This represents the logical port or logical disk identifier.

The shelf ID is 2, so the drive is in shelf 2 (A is correct).

The bay ID is 3, so the drive is in bay 3 (B is correct).

C. The drive is in bay 2: The bay ID is explicitly specified as 3, not 2.

D. The drive is in shelf 1: The shelf ID is clearly given as 2, not 1.

NetApp Hardware Universe documentation provides details on disk naming conventions.

The "ONTAP Disk Management Guide" includes a full explanation of disk IDs and their interpretation.

How to Interpret Disk Identifier 1.2.3.L1:Why Other Options Are Incorrect:References:

To invoke AutoSupport in ONTAP, the following tools can be used:

How to use:Run the command:

1. CLI (Command Line Interface)python

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autosupport invoke -node -type all

This triggers AutoSupport to collect and send logs and system information.

How to use:Log in to the Active IQ portal and use its interface to request an AutoSupport message from the connected ONTAP systems.

2. NetApp Active IQ website

A. NetApp Cloud Insights:

This tool is used for monitoring and performance analysis, not for triggering AutoSupport messages.

D. the SmartSolve tool:

SmartSolve is used for case resolution guidance but does not invoke AutoSupport.

Why Other Options Are Incorrect:

"ONTAP AutoSupport Guide" provides instructions for invoking AutoSupport via CLI and Active IQ.

References:

If a node is not booting, the following methods can be used to access the system for troubleshooting:

What it does:The SP provides out-of-band management access to the node, even if the node is not booting.

How to use:

Connect to the SP using SSH or a direct console connection.

Use SP commands to gather logs or perform diagnostics.

1. Service Processor (SP)

What it does:The serial console provides direct access to the node's bootloader or maintenance mode.

How to use:

Connect to the serial port using a terminal emulator.

Use console commands to interact with the system.

2. Serial Console

A. node management port:

The node management interface is only accessible if the node is booted and ONTAP is running.

B. cluster management port:

The cluster management interface requires the cluster to be operational, which is not possible if the node is not booting.

Why Other Options Are Incorrect:

NetApp "Service Processor and Serial Console Guide" provides instructions for accessing a non-booting node.

References:

If a disk is marked as failed, the Failure Byte on the disk indicates that the disk has been flagged for failure. This can be cleared using the following methods:

What it does:Physically remove the disk from the shelf and reseat it. This action can trigger the system to re-evaluate the disk's status and clear the Failure Byte if the failure was transient or due to connection issues.

1. Reseat the Disk

What it does:Using the disk unfail command in maintenance mode clears the Failure Byte and returns the disk to service.

Command Example:

2. Unfail the Diskdisk unfail

A. Power cycle the disk shelf:

Power cycling the shelf may clear other transient hardware issues but does not specifically clear the Failure Byte.

C. Update the disk firmware:

While updating firmware can prevent future issues, it does not address disks already marked as failed.

Why Other Options Are Incorrect:

NetApp "Disk Maintenance Guide" explains procedures to address failed disks.

The "ONTAP Command Reference" covers the disk unfail command for clearing the Failure Byte.

References:

A. Ignoring NetApp Active IQ health risks

Explanation:NetApp Active IQ provides proactive monitoring and alerts for system health risks, including risks related to WAFL inconsistencies. Ignoring these alerts can lead to unresolved issues such as metadata corruption, hardware failures, or system misconfigurations, increasing the chances of WAFL inconsistencies.

Examples of Active IQ Risks:

Disk health warnings.

High write latency or metadata bottlenecks.

Aggregates running out of space.

C. Using outdated disk firmware

Explanation:Outdated disk firmware can cause performance issues, drive failures, or incorrect handling of I/O operations, potentially leading to WAFL inconsistencies. Disk firmware updates often include fixes for critical issues that improve reliability and prevent data corruption.

Importance:Keeping firmware updated ensures compatibility with ONTAP and minimizes risks of disk-level errors that can propagate to WAFL.

Why the Other Options Are Incorrect:

B. Constantly running at high load:

Running at high load can impact performance but does not directly cause WAFL inconsistencies. WAFL is designed to handle high I/O loads efficiently.

D. Upgrading frequently:

Frequent upgrades, when performed correctly, do not increase the chances of WAFL inconsistencies. However, improperly executed upgrades or skipping recommended steps might introduce risks.

References:

NetApp Knowledge Base: Articles on Active IQ health checks and disk firmware management.

ONTAP System Administration Guide: Recommendations for preventing WAFL inconsistencies.

 Overview of IOM 12 Module:

The IOM 12 module is used in NetApp storage shelves for SAS connectivity.

 Key Features of IOM 12:

SAS Ports: The IOM 12 module has four SAS ports (two IN and two OUT) to support daisy-chaining of shelves and provide redundancy.

ACP (Alternate Control Path): The IOM 12 includes an Ethernet port for ACP, which is used for out-of-band management and monitoring of the storage shelves.

 Elimination of Other Options:

Option A is incorrect because the module has four SAS ports, not two.

Option C is incorrect because the module does include an Ethernet port for ACP.

 NetApp Reference Documentation:

"NetApp Hardware Universe" lists the specifications of the IOM 12 module, including its SAS and ACP capabilities.

The "ONTAP Shelf Installation Guide" discusses ACP and its role in shelf management.

 Explanation of RAID Label Versions:

Disks in ONTAP systems contain metadata known as RAID labels. These labels store critical information such as ownership, aggregate membership, and versioning.

The error indicates a mismatch between the RAID label version on the disk and the supported versions of the ONTAP system.

 Why Option D Is Correct:

If a disk has a RAID label created by a newer version of ONTAP (e.g., version 16) and is then inserted into a system running an older version of ONTAP (e.g., supporting versions 14-15), the label will not be recognized.

This mismatch causes ONTAP to reject the disk.

 Resolution:

Upgrade the ONTAP version to match the RAID label on the disk.

Alternatively, zero the disk to reset its RAID label, but this will erase all data on the disk.

 NetApp Reference Documentation:

The "ONTAP Disk Management Guide" and "ONTAP Compatibility Matrix" explain RAID label versions and compatibility issues when moving disks between ONTAP systems.