PAS-C01 Operations and Maintenance Practice Test 31 — 15 Questions

Question 1

A company runs SAP S/4HANA on AWS with a High Availability (HA) cluster spanning two Availability Zones (us-east-1a and us-east-1b). The cluster uses an Amazon FSx for NetApp ONTAP file system for the global transport directory. Recently, the cluster experienced a split-brain situation, leading to data corruption. The administrator wants to prevent this from recurring. The current setup uses a single FSx file system mounted on both cluster nodes. What should the administrator do to prevent split-brain?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Configure a STONITH (Shoot The Other Node In The Head) mechanism using AWS Lambda. STONITH (Shoot The Other Node In The Head) is a fencing mechanism that ensures a failed node is forcefully isolated or powered off before the other node takes over, preventing split-brain scenarios in High Availability clusters. Option A is incorrect because adding a third node increases complexity without addressing the root cause of split-brain. Option B is incorrect because increasing memory does not affect cluster communication or fencing. Option D is incorrect because cross-region replication is for disaster recovery, not for preventing split-brain.

Answer

Add a third cluster node in a third Availability Zone

Answer

Increase the memory on both EC2 instances

Answer

Set up cross-region replication for the FSx file system

Question 2

A company runs a critical SAP HANA database on an m5.24xlarge EC2 instance. The operations team notices that the database performance degrades during peak hours. Which AWS service should be used to identify whether the instance is experiencing CPU throttling due to CPU credit exhaustion?

Accepted Answer

Use CloudWatch to monitor the CPUUtilization metric.. CloudWatch CPUUtilization measures the actual CPU usage of the EC2 instance. For m5 instances, which are dedicated performance instances, there is no CPU credit concept, so monitoring CPUCreditBalance (option D) is irrelevant. The operations team can set a CloudWatch alarm on CPUUtilization to detect when CPU usage is high during peak hours, indicating potential performance degradation. Option A (CloudTrail) logs API calls, not performance metrics. Option B (Trusted Advisor) provides best practice recommendations but does not offer real-time CPU monitoring. Therefore, CloudWatch CPUUtilization is the appropriate service to identify CPU throttling issues.

Answer

Use CloudTrail to review the EC2 instance launch configuration.

Answer

Use AWS Trusted Advisor to check for instance performance issues.

Answer

Use CloudWatch to monitor the CPUCreditBalance metric.

Question 3

An SAP administrator is troubleshooting an issue where SAP application servers are unable to connect to the SAP HANA database. The database is running on an EC2 instance in a private subnet. The application servers are in a different VPC connected via VPC peering. The security group for the database instance allows TCP port 3$15$13 from the application server security group. Which additional configuration is MOST likely required?

Accepted Answer

Enable DNS resolution for the VPC peering connection.. VPC peering does not automatically enable DNS resolution for hostnames across peered VPCs. The application servers need to resolve the database's private DNS hostname to its private IP. By default, DNS resolution for peered VPCs is disabled. Enabling DNS resolution on the VPC peering connection allows the application servers to resolve the database's hostname, which is essential for connectivity. Option A is incorrect as the security group already allows the port; Option B is incorrect because the route tables already handle traffic via the peering connection; Option C is incorrect because network ACLs are not the core issue—the problem is DNS resolution, not NACL rules.

Answer

Modify the security group to allow traffic from the application server subnet CIDR.

Answer

Update the route tables to add a route to the database subnet.

Answer

Add a rule to the network ACL to allow inbound traffic on port 3$15$13.

Question 4

A company is using AWS Systems Manager to automate patching of SAP EC2 instances. The patching fails for some instances with the error 'Unable to retrieve SSM Agent registration'. What is the MOST likely cause?

Accepted Answer

The instance does not have outbound internet access or a VPC endpoint for Systems Manager.. The error 'Unable to retrieve SSM Agent registration' indicates that the SSM Agent cannot communicate with the Systems Manager service. This typically occurs when the instance lacks outbound internet access or a VPC endpoint for Systems Manager. Option A is incorrect because a patching window timeout would produce a different error. Option B is incorrect because the IAM role permissions issue would cause an access denied error, not a registration failure. Option D is incorrect because the SSM Agent runs on EC2 instances, not containers, and the error is unrelated to container environments.

Answer

The patching window is too short and the instance times out.

Answer

The IAM role attached to the instance does not have permissions to list patches.

Answer

The SSM Agent is not installed because the instance is running in a container.

Question 5

An SAP system running on AWS uses a Multi-AZ RDS for SAP ASE database. The operations team notices that the database failover took longer than expected during a recent outage. What should the team investigate to reduce failover time?

Accepted Answer

Check for long-running transactions that delay the failover.. Multi-AZ failover time is primarily affected by the time required to complete in-flight transactions and apply redo logs to the standby. Long-running transactions can delay failover because they must be completed or rolled back before the standby can become the primary. Option A is incorrect because increasing storage may improve I/O performance but does not directly reduce failover time. Option B is incorrect because the standby must be in a different Availability Zone for Multi-AZ. Option D is incorrect because Multi-AZ RDS uses synchronous replication, not asynchronous.

Answer

Increase the allocated storage for the database to improve I/O performance.

Answer

Ensure that the standby instance is in the same Availability Zone as the primary.

Answer

Verify that the database is using asynchronous replication.

Question 6

A company runs SAP on AWS and uses a shared file system via Amazon EFS for transport files. Recently, the SAP system experienced slowness when importing transports. The CloudWatch metrics show high BurstCreditBalance for the EFS file system. What action should be taken to improve performance?

Accepted Answer

Enable Max I/O performance mode on the EFS file system.. When BurstCreditBalance is high, it indicates that the file system is not using its burst credits, meaning it is operating at baseline throughput. To improve performance, enable Max I/O performance mode on the EFS file system, which provides higher throughput and IOPS. Option B is incorrect because changing to General Purpose mode does not increase throughput; it may even reduce performance. Option C is incorrect because encryption does not affect throughput. Option D is incorrect because BurstCreditBalance cannot be purchased; it is automatically accrued and consumed.

Answer

Change the performance mode to General Purpose.

Answer

Enable encryption at rest to improve data transfer speed.

Answer

Increase the BurstCreditBalance by purchasing additional credits.

Question 7

An SAP Basis administrator needs to apply an OS-level security patch to a fleet of SAP EC2 instances running Red Hat Enterprise Linux. The instances are part of an Auto Scaling group. Which approach is the MOST efficient and minimizes downtime?

Accepted Answer

Create a new AMI with the patch applied, update the launch template, and perform a rolling update via Auto Scaling.. The most efficient and minimizes downtime because it uses a rolling update strategy. By creating a new AMI with the patch applied and updating the launch template in the Auto Scaling group, instances are gradually replaced without stopping all at once. Option A is incorrect because manually terminating instances is not efficient and doesn't leverage Auto Scaling automation. Option B is incorrect because stopping all instances to apply a patch causes downtime. Option C is incorrect because while Systems Manager Patch Manager can apply patches, simultaneous patching without a rolling update risks service disruption, especially if reboots are required. The rolling update via Auto Scaling ensures high availability.

Answer

Create a custom AMI and manually terminate each instance to launch new ones.

Answer

Stop all instances, apply the patch using a script, and restart them.

Answer

Use AWS Systems Manager Patch Manager to apply the patch to all instances simultaneously.

Question 8

A company runs SAP HANA on AWS and needs to perform a backup of the HANA database to Amazon S3. Which AWS service should be used to orchestrate the backup and ensure consistency?

Accepted Answer

AWS Backup with pre- and post-backup scripts for application-consistent backups.. AWS Backup supports SAP HANA on EC2 with pre- and post-scripts for application-consistent backups. Option B is wrong because S3 Lifecycle policies manage object lifecycle, not backups. Option C is wrong because DLM manages EBS snapshots, not application-consistent backups. Option D is wrong because Storage Gateway is for hybrid storage, not SAP HANA backups.

Answer

Amazon S3 Lifecycle policies to transition backups to Glacier.

Answer

Amazon Data Lifecycle Manager (DLM) to schedule EBS snapshots.

Answer

AWS Storage Gateway file gateway to back up to S3.

Question 9

During a disaster recovery test, an SAP administrator finds that the SAP application cannot connect to the replicated HANA database in the DR region. The replication is done using SAP HANA System Replication. What is the MOST likely cause?

Accepted Answer

The application connection string still points to the primary database endpoint.. In SAP HANA System Replication, the database is replicated to the DR region, but the SAP application's connection string must be updated to point to the DR database endpoint. Without this update, the application will still try to connect to the primary database endpoint, which is not accessible during the DR test. Option A is incorrect because the replication link being down does not cause the application connection failure; the issue is the connection string. Option C is incorrect because even if the DR database is not fully synchronized (which is typical for async replication), the application could still connect to the DR database if the connection string were correct. Option D is incorrect because simply restarting the application server does not update the connection string; the endpoint configuration needs to be changed.

Answer

The replication link is down because the source database is not accessible.

Answer

The HANA database in the DR region is not synchronized due to network latency.

Answer

The application server needs to be restarted to recognize the new database.

Question 10

An SAP system is experiencing high disk I/O latency. The operations team checks the Amazon CloudWatch metrics and finds that the Average Queue Length for the EBS volumes is consistently above the recommended threshold. Which action should be taken to address this issue?

Accepted Answer

Increase the provisioned IOPS for the EBS volumes.. Increasing the provisioned IOPS for the EBS volumes directly increases the number of I/O operations the volume can handle, reducing the average queue length. Option A is incorrect because st1 volumes are optimized for throughput, not IOPS. Option C is incorrect because EBS encryption does not improve I/O performance and may introduce a slight overhead. Option D is incorrect because increasing volume size does not directly affect queue length; for gp2 volumes, it only increases baseline IOPS indirectly via burst credits, but it is not a reliable method to reduce queue length.

Answer

Change the volume type to Throughput Optimized HDD (st1).

Answer

Enable EBS encryption to improve I/O performance.

Answer

Increase the volume size to improve I/O performance.

Question 11

A company runs SAP on AWS and wants to automate the monitoring of SAP system health. Which TWO AWS services can be used together to achieve this? (Choose TWO.)

Accepted Answer

AWS Lambda. Options C (AWS Lambda) and D (Amazon CloudWatch) are correct. CloudWatch can collect custom metrics from SAP systems, and Lambda can process and act on those metrics to automate monitoring. Option A (AWS Config) is for compliance and configuration tracking, not monitoring. Option B (EC2 Auto Scaling) is for scaling instances, not monitoring. Option E (SQS) is a message queue service, not used for monitoring.

Answer

AWS Config

Answer

Amazon EC2 Auto Scaling

Answer

Amazon Simple Queue Service (SQS)

Question 12

An SAP administrator is troubleshooting a performance issue where the SAP application is slow. The administrator suspects that the EBS volumes are not meeting performance requirements. Which THREE metrics should be examined in Amazon CloudWatch to confirm this? (Choose THREE.)

Accepted Answer

VolumeQueueLength. Options A, B, and C are correct. VolumeQueueLength indicates the number of pending I/O requests, which can point to performance bottlenecks. VolumeReadBytes and VolumeWriteBytes measure the throughput of read and write operations, respectively. Option D (CPUCreditBalance) is related to CPU credits for burstable instances, not EBS performance. Option E (BurstBalance) tracks EBS burst credits but is not among the primary metrics to confirm EBS volume performance issues; the three chosen metrics directly address I/O queue depth and throughput.

Answer

CPUCreditBalance

Answer

BurstBalance

Question 13

A company is planning to migrate its SAP workloads to AWS. Which THREE AWS services are commonly used to set up a secure network connectivity between on-premises and AWS? (Choose THREE.)

Accepted Answer

AWS Transit Gateway. Options A, B, and C are correct. AWS VPN, Direct Connect, and Transit Gateway are used for hybrid connectivity. Option D is not correct because VPC Peering is for VPC-to-VPC, not on-premises. Option E is not correct because Client VPN is for individual clients.

Answer

VPC Peering

Answer

AWS Client VPN

Question 14

A company runs its SAP ERP system on AWS using a multi-tier architecture. The SAP application servers are in an Auto Scaling group across two Availability Zones, and the SAP HANA database runs on a single large EC2 instance (r5.24xlarge) with 768 GB of memory and EBS Provisioned IOPS SSD (io1) volumes. The operations team recently noticed that the database performance degrades intermittently during peak business hours. CloudWatch metrics show that the database instance's CPU utilization remains below 40%, but the ReadLatency and WriteLatency for the EBS volumes spike above 10 ms during these periods, and the VolumeQueueLength metric increases significantly. The database instance uses a single EBS volume for /hana/data and another for /hana/log. The team has already verified that there are no network bottlenecks and that the SAP application servers are not overwhelming the database with queries. What is the MOST likely cause of the latency spikes, and what action should be taken?

Accepted Answer

Upgrade the EC2 instance to a Nitro-based instance type like r5b.24xlarge, which provides higher EBS bandwidth and lower latency.. The symptoms indicate that the EBS volumes are experiencing queueing due to insufficient I/O performance. The r5.24xlarge instance uses the Xen hypervisor, which has lower EBS bandwidth compared to Nitro-based instances like r5b.24xlarge. Upgrading to a Nitro instance provides dedicated EBS bandwidth and lower latency, addressing the latency spikes. Option A is incorrect because st1 (throughput optimized) is not suitable for low-latency database workloads; it is designed for large sequential I/O. Option B is incorrect because adding more application servers would increase the database load, exacerbating the issue. Option C is incorrect because EBS encryption does not improve I/O performance.

Answer

Change the EBS volume type from io1 to st1 for higher throughput.

Answer

Add more SAP application servers to distribute the load and reduce database contention.

Answer

Enable EBS encryption on the volumes to improve I/O performance.

Question 15

A company has deployed SAP on AWS with a shared file system using Amazon EFS for the /sapmnt directory. The EFS file system is mounted on all SAP application servers. Recently, users reported that the SAP system is slow when accessing reports that are stored as PDF files in the /sapmnt directory. The operations team checks the CloudWatch metrics and finds that the EFS file system's PercentIOLimit metric is consistently at 100% during peak hours. The file system is using the General Purpose performance mode. The team also notices that the BurstCreditBalance is decreasing over time. What action should be taken to resolve this performance issue?

Accepted Answer

Increase the size of the EFS file system to improve performance.. Increasing the size of the EFS file system increases the baseline throughput (which scales at 50 MiB/s per TB of storage) and also increases the rate at which burst credits are earned, helping to reduce the percent I/O limit and rebuild the burst credit balance. Option A is wrong because lifecycle management only moves files to Infrequent Access, which does not improve I/O performance and may add latency. Option C is wrong because enabling Provisioned Throughput does not increase the burst credit balance; it provides a fixed throughput independent of credits, but the wording is misleading. Option D is wrong because the EFS performance mode cannot be changed after creation; it is set when the file system is created.

Answer

Enable EFS lifecycle management to move infrequently accessed files to Infrequent Access storage class.

Answer

Increase the burst credit balance by enabling throughput mode.

Answer

Switch the EFS performance mode to Max I/O to get higher throughput.