SK0-005 Practice Test 8 — 10 Questions

Question 1

Refer to the exhibit. An administrator receives reports that a web application is returning HTTP 502 errors. The administrator examines the Nginx error log on the reverse proxy server and sees the following. Which of the following is MOST likely causing the errors?

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

Accepted Answer

The upstream server at 10.0.1.25:8080 refuses connections.. Option A is correct because the error 'Connection refused' indicates the upstream server (10.0.1.25:8080) is not accepting connections, typically because the backend service is down or the port is closed. Option B is incorrect because if Nginx were not running, no such log entry would be generated. Option C is incorrect because the client's DNS resolution is not involved after Nginx has already attempted to contact the upstream IP. Option D is incorrect because a firewall blocking outbound connections would cause a timeout, not a 'Connection refused' message.

Answer

The Nginx service is not running.

Answer

The firewall on the reverse proxy is blocking port 80.

Answer

The client's DNS cannot resolve example.com.

Question 2

A VMware ESXi host runs six virtual machines, each configured with 8GB of RAM, totaling 48GB allocated. The host physically has 32GB of RAM, and memory overcommitment is enabled. Recently, a critical VM experienced severe performance degradation during peak hours, with the guest OS showing high memory pressure and balloon driver activity, while other VMs showed moderate usage. Which of the following actions will BEST resolve the issue without compromising other VMs?

Accepted Answer

Configure a memory reservation of 8GB for the critical VM.. Option B (Set a memory reservation equal to its configured 8GB on the critical VM) is correct because it guarantees physical RAM for that VM, preventing the balloon driver from reclaiming its memory and reducing hypervisor swapping. Option A (Increase host RAM) would solve it broadly but is not the most immediate, targeted action and may not be feasible. Option C (Disable balloon driver on all VMs) could cause host swapping, degrading all VMs. Option D (Reduce CPU limits) does not address memory contention.

Answer

Purchase and install an additional 32GB of physical RAM in the host.

Answer

Disable the VMware balloon driver on all virtual machines.

Answer

Reduce the CPU limit on the non-critical VMs during peak hours.

Question 3

To comply with company security policies, a server administrator must disable all unnecessary services on a newly deployed Windows Server 2019. The server will only act as a file server with no web hosting role. Which service should be disabled?

Accepted Answer

World Wide Web Publishing Service. Option C is correct because the World Wide Web Publishing Service (W3SVC) is part of IIS and is not required for a file server role. Leaving it running increases the attack surface. Option A (DNS Server) might be used if the server provides name resolution, but it is not mentioned. Option B (DHCP Server) is also not specified as needed. Option D (Server service) is essential for file sharing and should not be disabled.

Answer

DHCP Server service

Answer

Server service

Answer

DNS Server service

Question 4

Refer to the exhibit. A Linux server is reporting slow I/O on the root filesystem. Which of the following actions should the administrator take to resolve the immediate storage bottleneck?

Accepted Answer

Move non-essential data from / to /backup.. Option B is correct because moving non-essential data from the nearly full root filesystem to /backup (which has ample space) quickly alleviates the space shortage and I/O pressure. Option A is wrong because resizing /dev/sda1 may require downtime and complex partitioning operations; it is not an immediate fix. Option C is wrong because deleting log files may free some space but might also delete valuable diagnostic data and may not be sufficient. Option D is wrong because changing the RAID level of /dev/sda is a fundamental hardware change that does not address the immediate space issue and could be destructive.

Answer

Delete log files in /var/log.

Answer

Resize /dev/sda1 to 30G.

Answer

Change the RAID level of /dev/sda.

Question 5

A user attempts to access a shared folder named \Server\Finance. The share permissions are set to 'Everyone – Full Control'. The NTFS permissions on the folder grant the user 'Read & Execute' but deny 'Write'. What is the user's effective permission when accessing the share over the network?

Accepted Answer

Read & Execute. When share and NTFS permissions combine, the most restrictive of the two applies. Share gives Full Control, NTFS gives Read & Execute, so effective access is Read & Execute.

Answer

Full Control

Answer

Write

Answer

No Access

Question 6

Refer to the exhibit. A server administrator configured iptables rules on a Linux server. Immediately afterward, they are unable to connect to the server via SSH. The output of 'iptables -L INPUT -n' is shown. What is the most likely cause of the connectivity issue?

Accepted Answer

The DROP rule for port 22 appears before the ACCEPT rule, causing all SSH packets to be dropped.. iptables processes rules in order. The DROP rule for destination port 22 appears before the ACCEPT rule, so all incoming SSH packets are dropped before the ACCEPT rule can permit new connections.

Answer

The last DROP rule blocks all traffic, including established SSH sessions.

Answer

The default INPUT policy is set to ACCEPT, allowing all traffic.

Answer

The ACCEPT rule for port 22 is missing the ESTABLISHED state, preventing return traffic.

Question 7

An administrator needs to remotely manage several Linux servers securely without using passwords. Which of the following is the BEST method?

Accepted Answer

Use SSH with key-based authentication.. Option C is correct because SSH with key-based authentication provides strong, password-less remote access. Option A is wrong because RDP is primarily used on Windows, not typical for Linux. Option B is wrong because Telnet is insecure, and SSH tunneling does not make Telnet secure. Option D is wrong because VNC is less secure and not designed for efficient server administration.

Answer

Use Telnet with SSH tunneling.

Answer

Use VNC with a strong password.

Answer

Use RDP with certificate-based authentication.

Question 8

A server administrator notices that a database server is experiencing high CPU usage at specific times of the day. After checking logs, the administrator finds that a report generation task scheduled at those times is causing the issue. The task cannot be rescheduled or optimized further. Which of the following actions should the administrator take to ensure the server remains responsive for other applications during peak usage?

Accepted Answer

Configure the task to run at a lower priority.. Option D is correct because lowering the priority (nice value) of the task allows other processes to utilize the CPU without being blocked. Option A is wrong because adding vCPUs does not guarantee other processes will get CPU time if the task consumes all available cycles. Option B is wrong because processor affinity only pins a process to a specific CPU core but does not change its scheduling priority. Option C is wrong because replacing hardware is not immediate and may not solve scheduling contention.

Answer

Add more virtual CPUs to the server's VM.

Answer

Move the database to a server with faster CPU cores.

Answer

Configure processor affinity to dedicate a core to the database process.

Question 9

A company is planning to deploy a new web application on multiple servers behind a load balancer. The application requires consistent session data across all servers for seamless user experience. Which of the following solutions would BEST meet this requirement?

Accepted Answer

Store session data in a shared, high-performance in-memory data store like Redis.. Option B is correct because a shared in-memory data store like Redis provides low-latency access to session data for all servers, ensuring consistency and high availability. Option A is wrong because round-robin DNS does not handle session persistence. Option C is wrong because sticky sessions tie a user to one server; if that server fails, the session is lost and consistency is not maintained across servers. Option D is wrong because synchronous database replication adds latency and complexity, making it less suitable for high-performance web applications.

Answer

Configure each web server to store sessions locally and use sticky sessions on the load balancer.

Answer

Use round-robin DNS to distribute traffic.

Answer

Implement database session storage with synchronous replication between servers.

Question 10

A server administrator receives an alert that a critical server's disk is almost full. Upon investigation, the administrator finds a large log file that has grown significantly. The log file is rotated daily, but today's rotation failed. Which command should the administrator use FIRST to free up space immediately?

Accepted Answer

> /var/log/large.log to truncate the file.. Option A is correct because truncating the file to zero size instantly reclaims disk space without removing the file, which could cause issues if processes still have it open. Option B is wrong because deleting the file will not free space if any process holds an open file handle. Option C is wrong because moving the file has similar issues as deletion. Option D is wrong because running logrotate might fail if the disk is full or if the rotation script is broken; truncation is quicker and safer under pressure.

Answer

logrotate -f /etc/logrotate.conf to force log rotation.

Answer

rm -rf /var/log/large.log to delete the file.

Answer

mv /var/log/large.log /backup/ to move the file.