CV0-004 Operations and Support Practice Test 3 — 15 Questions

Question 1

A cloud administrator is troubleshooting connectivity issues between two virtual networks in a public cloud. The networks are in the same region but different VPCs. Both VPCs have route tables and security groups configured. Instances in VPC A cannot ping instances in VPC B. Which of the following is the most likely cause?

Accepted Answer

VPC peering is not established between the two VPCs.. VPC peering is a direct network connection between two VPCs that enables routing of traffic using private IPv4 or IPv6 addresses. Without an established VPC peering connection, instances in different VPCs cannot communicate, even if they are in the same region. Since the question states the VPCs are separate and no peering is mentioned, this is the most likely root cause of the connectivity failure.

Answer

The instances are not assigned public IP addresses.

Answer

Security groups are blocking ICMP traffic.

Answer

Network ACLs are not configured to allow the traffic.

Question 2

A company uses a cloud-based backup solution for its virtual machines. The backup policy specifies daily backups with a retention of 30 days. The backup administrator notices that backups are failing with an error indicating insufficient storage space in the backup repository. Which of the following is the most likely reason for this issue?

Accepted Answer

The retention period is too long for the available storage.. The error indicates insufficient storage space in the backup repository. With a daily backup policy and a 30-day retention period, the repository must accommodate at least 30 full backups (or the equivalent incremental/differential chain). If the repository's capacity is less than the total size of 30 backups, the retention period exceeds the available storage, causing failures. This is the most direct cause of the error.

Answer

The backup frequency is too low.

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Compression is not enabled on the backup.

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The backup window is too short.

Question 3

A cloud administrator is deploying a new application that requires low latency between two virtual machines. The VMs are in the same cloud region but in different availability zones. The administrator notices higher latency than expected. Which of the following is the most effective way to reduce latency?

Accepted Answer

Move both VMs to the same availability zone.. Moving both VMs to the same availability zone reduces the physical network distance and eliminates the latency introduced by inter-zone routing. In cloud providers, availability zones are distinct data centers with separate power and networking, so traffic between zones traverses additional switches and fiber, adding microseconds to milliseconds of latency. Placing VMs in the same zone keeps traffic within a single data center fabric, minimizing hop count and propagation delay.

Answer

Assign larger instance types to both VMs.

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Use a VPN connection between the VMs.

Answer

Place both VMs in the same placement group.

Question 4

A company is migrating its on-premises database to a cloud-based managed database service. The database is currently 500 GB and is expected to grow by 10% monthly. Which TWO factors should the company consider when selecting the storage type?

Accepted Answer

Encryption at rest requirements.. Encryption at rest is a critical consideration when selecting storage for a cloud-based managed database service, as it ensures data is encrypted when stored on disk. Many cloud providers offer transparent data encryption (TDE) or server-side encryption with customer-managed keys (CMKs), and the storage type must support these features to meet compliance requirements.

Answer

Backup frequency and retention.

Answer

Physical location of the data center.

Answer

Operating system compatibility with the storage.

Question 5

A cloud engineer is troubleshooting a performance issue with a web application that uses a cloud load balancer and multiple backend instances. Users report intermittent slow responses. The engineer reviews metrics and finds that CPU utilization on backend instances stays below 50% but network throughput is near the instance limit. Which THREE actions should the engineer take to improve performance?

Accepted Answer

Distribute instances across multiple availability zones.. Distributing instances across multiple availability zones (AZs) improves fault tolerance and can reduce network congestion by spreading traffic across physically separate infrastructure. In this scenario, network throughput is near the instance limit, so adding instances in different AZs allows the load balancer to distribute traffic more evenly, preventing any single instance from being overwhelmed. This also leverages the load balancer's cross-zone load balancing capability, which can improve overall throughput and reduce latency for users.

Answer

Change the load balancing algorithm to least connections.

Answer

Increase the number of backend instances.

Question 6

A cloud administrator is trying to attach an EBS volume to an EC2 instance for a database migration. The attachment fails with the error shown in the exhibit. The volume contains critical data. Which of the following is the MOST appropriate action to take?

Accepted Answer

Detach the volume from instance 'i-0123ijkl' first, then attach to the new instance.. The error indicates the EBS volume is already attached to another EC2 instance (i-0123ijkl). An EBS volume can only be attached to one instance at a time in a standard attachment. The correct procedure is to first detach the volume from instance i-0123ijkl, then attach it to the target instance. This preserves the critical data without risk of corruption or data loss.

Answer

Create a new volume and copy the data from the existing volume.

Answer

Terminate instance 'i-0123ijkl' to release the volume.

Answer

Force-detach the volume from the other instance.

Question 7

A cloud administrator receives an alert that a virtual machine is unresponsive. The hypervisor shows the VM status as 'running'. Which of the following should the administrator check FIRST to diagnose the issue?

Accepted Answer

Access the VM's console to view the operating system screen.. When a VM is unresponsive but the hypervisor shows its status as 'running', the most direct way to determine if the guest OS has crashed or is stuck in a boot loop is to access the VM's console. This provides a direct view of the OS screen, allowing the administrator to see if the OS is hung, at a login prompt, or displaying an error, which is the first step in isolating the issue before checking network or resource configurations.

Answer

Verify the security group rules for the VM's subnet.

Answer

Review the hypervisor's CPU and memory utilization for the VM.

Answer

Check the virtual network interface for disconnection.

Question 8

An organization is migrating a legacy application to a public cloud. The application requires a static IP address that does not change after a VM is stopped. Which of the following should the cloud architect use to meet this requirement?

Accepted Answer

Reserved IP address. A reserved IP address is a static, persistent public IP that remains assigned to a VM even when the VM is stopped or deallocated. In public cloud platforms like Azure, a reserved IP (or static IP) is explicitly set to not change across VM lifecycle events, meeting the requirement for a fixed address that survives stop/deallocate operations.

Answer

Elastic IP address

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Ephemeral IP address

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Floating IP address

Question 9

A company uses a cloud-based load balancer to distribute traffic to a fleet of web servers. Users report intermittent timeouts. The administrator reviews the load balancer logs and notices that one backend server has a significantly higher error rate than the others. Which of the following is the BEST course of action?

Accepted Answer

Drain connections to the unhealthy server and troubleshoot its configuration.. Option B is correct because draining connections from the unhealthy server allows the load balancer to stop sending new traffic to it while existing sessions complete, preventing further timeouts. Troubleshooting the server's configuration addresses the root cause of the high error rate, such as misconfigured web server software, resource exhaustion, or application bugs. This approach follows the principle of isolating and resolving the faulty component rather than masking the issue with workarounds.

Answer

Immediately add two more backend servers to distribute the load.

Answer

Enable sticky sessions on the load balancer to maintain user sessions.

Answer

Increase the health check interval for all servers to reduce false positives.

Question 10

Which TWO of the following are best practices for securing an API gateway in a cloud environment?

Accepted Answer

Implement rate limiting to control the number of requests per client.. Option A is correct because rate limiting is a fundamental security control for API gateways. It mitigates abuse and denial-of-service (DoS) attacks by restricting the number of requests a client can make within a specified time window, typically enforced via token bucket or leaky bucket algorithms. This ensures fair resource usage and protects backend services from being overwhelmed.

Answer

Expose the API endpoints without authentication for ease of integration.

Answer

Return detailed error messages including stack traces to help developers.

Answer

Disable HTTPS to reduce latency.

Question 11

A load balancer log entry shows the above for a request. What is the MOST likely cause of the 504 error?

Accepted Answer

The backend server took too long to respond to the request.. A 504 Gateway Timeout error from a load balancer indicates that the load balancer sent the request to a backend server but did not receive a timely response. The load balancer has a configured timeout value (often 30-120 seconds), and if the backend server fails to respond within that window, the load balancer terminates the connection and returns a 504. This is the most common cause of 504 errors in load-balanced environments.

Answer

The DNS resolution for the domain name has failed.

Answer

The requested resource does not exist on the backend server.

Answer

The load balancer's health check is misconfigured.

Question 12

A company runs a critical application on a single VM in a public cloud. The VM uses a 500 GB managed disk. The company takes daily snapshots of the disk for backup. The operations team notices that the snapshot creation time has increased from 5 minutes to over an hour over the past month. The VM's disk usage has remained stable at around 200 GB. The VM runs a database that writes logs to a separate data disk (100 GB) which is not snapshotted. Which of the following is the MOST likely cause of the increasing snapshot time?

Accepted Answer

High write activity (churn) on the OS disk causing more data to be captured in each snapshot.. The snapshot creation time has increased because of high write activity (churn) on the OS disk. Azure and other cloud platforms use a block-level incremental snapshot mechanism; when a disk has high churn, many blocks change between snapshots, forcing the snapshot process to read and store a large number of changed blocks even if the total used space remains stable. Since the VM runs a database that writes logs to a separate data disk (not snapshotted), the OS disk still experiences frequent writes from the database's log flushing or other system operations, causing the snapshot to capture many changed blocks and thus take longer.

Answer

The VM's used disk space has increased significantly, requiring larger snapshots.

Answer

The data disk is consuming space on the OS disk due to log file growth.

Answer

The backup software is compressing snapshots, causing CPU overhead and longer times.

Question 13

A cloud administrator is troubleshooting a performance issue in a virtualized environment. Which TWO metrics should be monitored to identify CPU contention on the hypervisor?

Accepted Answer

CPU ready time. CPU ready time (B) measures the time a virtual machine is ready to execute but must wait for the hypervisor to schedule it on a physical core. High ready time directly indicates CPU contention, as the VM is being starved of CPU cycles. CPU co-stopping time (E) occurs when multiple vCPUs in a single VM must wait to be scheduled simultaneously, which also signals CPU overcommitment and contention on the hypervisor.

Answer

Swap rate

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Memory ballooning

Answer

CPU utilization per core

Question 14

A cloud administrator runs the command shown in the exhibit on a storage node in a hyper-converged cluster. The node is experiencing intermittent I/O errors and degraded performance. Based on the SMART data, what is the most likely cause of the issue?

Accepted Answer

The disk has developed bad sectors and is likely failing.. The SMART data from the storage node shows attributes such as Reallocated_Sector_Count, Current_Pending_Sector, and Offline_Uncorrectable with non-zero values, which are definitive indicators of physical bad sectors on the disk. These bad sectors cause intermittent I/O errors and degraded performance because the disk must retry reads/writes or remap sectors, increasing latency. Option C is correct because this pattern directly points to a failing disk, not a network, filesystem, or RAID issue.

Answer

The storage network is experiencing high latency.

Answer

The filesystem is corrupted and requires a repair.

Answer

A RAID array is rebuilding, causing performance degradation.

Question 15

A cloud administrator for a large e-commerce company receives an alert that the response time of the production web application has increased by 300% in the last hour. The application is deployed on a Kubernetes cluster with three worker nodes, each running multiple pods. The administrator checks the Kubernetes dashboard and notices that one of the worker nodes has a CPU utilization of 95%, while the other two nodes are at 40%. The pods on the overloaded node are experiencing resource throttling. The application uses a deployment with a replica count of 6, and all pods are currently running. The administrator needs to resolve the performance issue quickly and prevent future occurrences. Which of the following actions should the administrator take FIRST?

Accepted Answer

Cordon and drain the overloaded node to redistribute its pods to other nodes.. C is correct because the immediate symptom is an overloaded node (95% CPU) causing resource throttling on its pods. Cordon and drain the node to safely evict its pods, allowing the Kubernetes scheduler to redistribute them to the underutilized nodes (40% CPU), which quickly resolves the performance bottleneck without adding unnecessary resources or changing the deployment configuration.

Answer

Increase the replica count from 6 to 12 to distribute load across more pods.

Answer

Add a new worker node to the cluster to increase overall capacity.

Answer

Modify the deployment to set resource requests and limits for CPU on all pods.