NetApp NS0-093 NetApp Accredited Hardware Support Engineer Exam Practice Test

Answer : A, B

A . NVMEM battery

Explanation: The NVMEM (Non-Volatile Memory) battery is a critical component for retaining data in case of a power failure. It is classified as a Field Replaceable Unit (FRU) in an AFF A220 system.

Replacement Notes:

Replacement can be performed by field engineers.

The system will typically alert you when the battery requires replacement.

B . mSATA boot device

Explanation: The mSATA (mini-SATA) boot device contains the ONTAP operating system and is also a FRU in the AFF A220. It is critical for the system's boot process and can be replaced if it becomes faulty.

Replacement Notes:

Boot devices are easily replaceable while ensuring ONTAP is reinstalled on the new device.

Why the Other Options Are Incorrect:

C . NVMe Flash Cache feature:

Incorrect. NVMe Flash Cache is not a physical FRU but a feature for accelerating read performance. It is implemented via software and NVMe-based SSDs, which are not specifically field replaceable in AFF A220.

D . Chassis fan:

Incorrect. The AFF A220 does not classify chassis fans as FRUs. These are usually part of the cooling system, but their replacement may require system shutdown or is integrated into the design.

NetApp Hardware Documentation: AFF A220 Component Replacement Guide.

NetApp Knowledge Base: Articles on replacing NVMEM batteries and mSATA boot devices.

Answer : C, D

Reverting to a previous ONTAP version requires careful preparation because ONTAP upgrades often introduce irreversible changes. To successfully revert, the following actions are needed:

C . Reinstall your boot media and install ONTAP 9.5 software

Explanation: You need to reinstall the older version of ONTAP (9.5) on the boot media because the current version (9.7) has been installed as part of the upgrade. The reinstallation ensures that the system boots with ONTAP 9.5.

Steps:

Boot the node into maintenance mode.

Perform the reinstallation using the appropriate ONTAP 9.5 image.

D . Wipe your config and restore from backup

Explanation: A revert requires wiping the configuration because ONTAP upgrades may have made changes to the cluster configuration or WAFL metadata. Restoring the configuration from a backup ensures consistency with the older ONTAP version.

Steps:

Back up the current cluster configuration before proceeding.

Use the restored backup after the revert is complete to reconfigure the system.

Why the Other Options Are Incorrect:

A . Revert from ONTAP 9.7 software to ONTAP 9.6 software and then to ONTAP 9.5 software:

Incorrect. ONTAP reverts must directly target the desired version. You cannot perform multi-step reverts.

B . Delete all Snapshot copies from the past two days:

Incorrect. Deleting Snapshot copies is not a prerequisite for reverting ONTAP. While older Snapshot copies might not be compatible with the reverted version, they do not need to be deleted before the revert.

NetApp Documentation: ONTAP Upgrade and Revert Procedures.

NetApp Knowledge Base: Steps for reinstallation and configuration restoration during a revert.

Answer : A, C

Possible Causes for 'No Disks' Error:

A (Incorrect SAS Cabling): If the SAS cables are incorrectly reconnected or swapped after replacing the boot device, the disks may not be detected because the physical connection to the shelves is compromised. Verifying and reseating the SAS cables is essential.

C (Lower ONTAP Version): If the node boots into an ONTAP version that is lower than the version previously used, it might not recognize the RAID labels or disk metadata created by the higher ONTAP version.

Why Other Options Are Incorrect:

B (Disks Marked as Failed): Disks that are marked as failed would still be visible in the system, though unusable.

D (Interconnect Down): An interconnect failure affects HA functionality but does not prevent a node from detecting its own disks.

NetApp Reference Documentation:

Refer to the 'ONTAP Boot Recovery Guide' and 'SAS Cabling Guide' for steps to resolve disk detection issu

Answer : B

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

Key Command:

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.

Why Other Options Are Incorrect:

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.

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

Answer : C

When using wafliron to repair WAFL inconsistencies on an aggregate, the aggregate becomes available after Phase 4 of the wafliron process is complete.

Phases of wafliron:

Phase 1: Initial scan to identify inconsistencies.

Phase 2: Corrects directory and inode structure issues.

Phase 3: Repairs blocks and metadata.

Phase 4: Completes final repairs and verification, after which the aggregate can be made available.

Why Other Options Are Incorrect:

A . when the administrator manually onlines the aggregate:

The aggregate cannot be manually brought online until wafliron completes Phase 4.

B . when wafliron is started:

Starting wafliron does not make the aggregate available; repairs need to be completed first.

D . after the mounting phase of wafliron is complete:

WAFLiron does not have a specific 'mounting phase.' Mounting happens after Phase 4 completes.

'NetApp WAFLiron Troubleshooting Guide' explains the availability of the aggregate after Phase 4.

NetApp Support documentation outlines the phases of wafliron and aggregate recovery.

Answer : B, D

To recover an inconsistent aggregate, the following tools can be used:

1. wafl_check

What it does: This tool is used to perform a consistency check on WAFL metadata. It identifies and attempts to fix WAFL inconsistencies in aggregates.

When to use: Run wafl_check after identifying WAFL inconsistencies to repair minor metadata issues.

2. wafliron

What it does: This tool repairs WAFL inconsistencies by reconstructing metadata. It is more powerful than wafl_check and should only be run under NetApp Support guidance, as improper use can result in data loss.

When to use: Use wafliron for severe WAFL inconsistencies that cannot be resolved by wafl_check.

Why Other Options Are Incorrect:

A . file check:

This is not a valid NetApp tool.

C . wafl snapiron:

While similar in name, snapiron is used for snapshot recovery, not aggregate recovery.

'ONTAP Aggregate Troubleshooting Guide' details the usage of wafl_check and wafliron.

NetApp Support documentation provides guidelines for recovering inconsistent aggregates.

Answer : A

A NetApp WAFL (Write Anywhere File Layout) inconsistency in a RAID-DP aggregate could occur in the following scenarios:

1. Two disks failing and a block error during reconstruction

Why this causes inconsistency:

RAID-DP is designed to handle up to two concurrent disk failures. However, if a block error occurs during the reconstruction process (e.g., unreadable data on the surviving disks), the RAID group cannot rebuild the lost data, leading to WAFL inconsistencies.

2. Two disks failing within seconds of each other

Why this causes inconsistency:

If two disks in the same RAID group fail nearly simultaneously (before the RAID-DP can reconstruct data from the first failed disk), the system cannot recover the data, resulting in WAFL inconsistencies.

Why Other Options Are Incorrect:

B . rebooting a node during a disk reconstruction:

Rebooting a node does not cause WAFL inconsistency because ONTAP ensures that RAID reconstructions resume upon reboot without data loss.

D . both party disks failing:

This is not a valid RAID-DP term.

'WAFL and RAID-DP Operations Guide' explains failure scenarios that could cause inconsistencies.

NetApp's 'Troubleshooting RAID Groups and Aggregates' covers recovery procedures for double-disk failures and reconstruction errors.