NetApp Accredited Hardware Support Engineer NS0-093 Exam Questions

Answer : A

When a volume is deleted in a NetApp ONTAP system, it is placed in the Volume Recovery Queue. By default, the volume remains in this recovery queue for 12 hours before being permanently deleted. This allows administrators to recover mistakenly deleted volumes within the set retention period.

Explanation of Default Behavior:

Volume Recovery Queue:

This is a feature in NetApp ONTAP that acts as a safety mechanism, providing a grace period for recovering deleted volumes.

The default retention period for volumes in the recovery queue is 12 hours, as confirmed by the NetApp KB: 'How to use the Volume Recovery Queue.'

How to Recover a Deleted Volume:

Administrators can recover a deleted volume as long as it remains in the recovery queue and the retention period has not expired.

Use the ONTAP CLI command:

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cluster::> volume recovery-queue recover -vserver <vserver_name> -volume <volume_name>

This command restores the volume back to its original state.

How to Check the Volume Recovery Queue:

To view volumes in the recovery queue and their expiration times, use:

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cluster::> volume recovery-queue show

Changing the Default Retention Period:

While the default period is 12 hours, it can be adjusted by administrators to fit specific organizational requirements. This is done via system settings or policies.

Why the Other Options Are Incorrect:

B . 48 hours: Incorrect. The default retention period is not 48 hours; it is 12 hours by default.

C . 72 hours: Incorrect. While a custom configuration could allow this, it is not the default.

D . 24 hours: Incorrect. Although this was previously thought to be the default, NetApp documentation explicitly states it is 12 hours.

NetApp Knowledge Base Article: 'How to use the Volume Recovery Queue'.

NetApp ONTAP Documentation: Volume Recovery and Data Management Procedures.

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 : C

To collect shelf logs for a DS4246 shelf in an ONTAP 9.12.1 system, you must invoke a diagnostic AutoSupport specifically targeting the storage subsystem. This action ensures that detailed storage logs, including shelf logs, are included in the AutoSupport bundle.

Steps to Collect Shelf Logs:

Use the following command:

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system node autosupport invoke -node <node_name> -type diagnostic -subsystem storage

Replace <node_name> with the name of the node experiencing the issue.

This command generates an AutoSupport message that includes logs related to storage subsystems, such as disk shelves and adapters.

Provide the AutoSupport case number to NetApp Support for further analysis.

Why Other Options Are Incorrect:

A . Provide the output of the nodeshell command rdfile /etc/log/shelflog:

While this command allows manual reading of shelf logs, it is not a recommended or comprehensive approach for collecting logs for NetApp Support cases.

B . Invoke an AutoSupport of type all using Active IQ Unified Manager:

This action generates a generic AutoSupport bundle, which may not include detailed shelf logs unless explicitly targeted.

D . Invoke a diagnostic AutoSupport with the subsystem log_files:

The log_files subsystem targets general system logs, not storage-specific logs like shelf logs.

'ONTAP 9 AutoSupport and Diagnostics Guide' outlines the use of the subsystem storage option for collecting shelf logs.

The 'Troubleshooting Storage Subsystems' documentation specifies diagnostic AutoSupport as the method for gathering shelf-related logs.

Answer : D

When a node panics in ONTAP, a kernel core file is generated. This core file contains information about the kernel's state at the time of the panic and is essential for debugging system crashes.

Key Details:

A kernel core file is produced during a node panic to capture information about the kernel, memory, and processes that led to the crash.

The core file is stored on the root aggregate by default and can be uploaded to NetApp Support using the autosupport invoke-core-upload command.

Why Other Options Are Incorrect:

A . mgwd core:

This is related to the Management Gateway daemon, which handles management traffic. It does not generate a core file during a panic.

B . user space core:

User space cores are generated for processes running in user space, not for kernel panics.

C . sync core:

Sync cores refer to synchronized cores for debugging but are not the primary type generated during a node panic.

'ONTAP Panic Troubleshooting Guide' specifies kernel core files as the output of a node panic.

'ONTAP Core File Management Guide' details the handling of kernel core files after a crash.

Answer : B, C

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

1. CLI (Command Line Interface)

How to use: Run the command:

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autosupport invoke -node <nodename> -type all

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

2. NetApp Active IQ website

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

Why Other Options Are Incorrect:

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.

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

Answer : A, D

FRUs on FAS9000 Supporting Replacement Without Takeover:

A (I/O Module): I/O modules can be replaced hot (without takeover) to maintain system uptime during hardware servicing.

D (NVRAM Module): NVRAM modules on FAS9000 can also be replaced without a node takeover, ensuring data integrity during replacement.

Why Other Options Are Incorrect:

B (DCPM Module): The DCPM (Data Center Power Management) module is not hot-swappable and requires a node takeover.

C (Caching Module): The caching module is integrated and typically requires a node takeover or power-down for replacement.

NetApp Reference Documentation:

Refer to the 'NetApp FAS9000 Hardware Service Guide' for supported FRU replacement procedures and operational constraints.

Answer : A, B

To determine whether an aggregate is WAFL (Write Anywhere File Layout) inconsistent, the following two commands can be used:

1. wafiron show

What it does: This command directly checks the WAFL consistency status of the specified aggregate. If an aggregate is WAFL inconsistent, it will report the inconsistency in the output.

How to use:

Run the command: wafiron show (replace with the name of the aggregate).

Look for indications of WAFL inconsistency in the output.

Why it's relevant: The wafiron utility is specifically designed to provide WAFL status and diagnostics. It is the most accurate and direct way to confirm whether an aggregate is inconsistent.

'WAFL Troubleshooting Guide' from NetApp highlights the wafiron show command as a primary tool for checking aggregate consistency.

2. node run --node <node> sysconfig --r

What it does: This command displays RAID information for all aggregates on the specified node. If an aggregate is WAFL inconsistent, it will be explicitly mentioned in the output.

How to use:

Run the command: node run --node <node> sysconfig --r.

Check the output for the phrase 'WAFL inconsistent' under the corresponding aggregate.

Why it's relevant: This command provides additional context, such as the RAID group details, which can help understand whether the inconsistency is isolated or part of a larger issue.

'ONTAP CLI Commands Guide' specifies sysconfig --r as a method to verify aggregate status, including WAFL consistency.

Why Other Options Are Incorrect:

C . storage aggregate show:

This command displays aggregate configuration and usage information but does not report WAFL inconsistency.

D . node run --node <node> sysconfig --a:

While this command shows detailed hardware configuration information, it does not include WAFL consistency status for aggregates.