1
CompTIA Secure
Infrastructure Specialist
(CSIS) – 150 Advanced
Practice Questions a well
detailed one 2025 /
2026 written and graded
A+ upgraded
Title: Comprehensive Advanced Practice Examination for the CompTIA Secure Infrastructure
Specialist (CSIS) Certification: 150 Mixed-Difficulty Multiple-Choice Questions Covering
Hardware, Networking, Security, Troubleshooting, and Infrastructure Protection Domains
, 2
Section 1: Hardware and Infrastructure Fundamentals (Questions 1–25)
1. A server administrator notices that a critical production server is experiencing intermittent
unexpected reboots. The system logs show no operating system errors or application crashes
prior to the reboots. Which hardware component is MOST likely the root cause?
A) Failing RAID controller battery
B) Overheating CPU due to thermal paste degradation
C) Failing power supply unit with voltage fluctuations
D) Corrupt BIOS firmware
-” detailed answer 100 % correct :-”C
Rationale: Intermittent unexpected reboots without OS or application errors are classic
symptoms of a failing power supply unit (PSU) that cannot maintain stable voltage delivery.
RAID controller battery failure typically causes cache data loss, not system reboots. CPU
overheating would generate thermal alerts in system logs. BIOS corruption would prevent
booting altogether.
2. Which RAID level provides the BEST balance of performance, capacity utilization, and fault
tolerance for a high-transaction database server with four identical disks?
A) RAID 0
B) RAID 1
C) RAID 5
D) RAID 10
-” detailed answer 100 % correct :-”D
Rationale: RAID 10 (RAID 1+0) provides both striping for performance and mirroring for fault
tolerance, offering the best balance for database workloads. It can sustain multiple disk failures
(one per mirror pair) and delivers excellent read/write performance. RAID 5 offers good capacity
utilization but has write performance penalties due to parity calculations.
3. A technician is troubleshooting a workstation that produces a series of beeps during POST
and fails to display anything on the monitor. The beep code pattern is three long beeps
followed by two short beeps. According to standard AMI BIOS beep codes, what does this
indicate?
A) Video card failure
B) Memory parity error
, 3
C) Keyboard controller failure
D) Base 64K memory failure
-” detailed answer 100 % correct :-”A
Rationale: AMI BIOS beep codes use specific patterns to indicate hardware failures. Three long
beeps followed by two short beeps typically indicates a video card failure or display adapter
issue. This is a common POST error that prevents the system from completing the boot process.
4. Which of the following memory module types is designed with a register between the
DRAM modules and the system's memory controller to reduce electrical loading and improve
stability in high-capacity configurations?
A) UDIMM
B) RDIMM
C) SODIMM
D) LRDIMM
-” detailed answer 100 % correct :-”B
Rationale: Registered DIMMs (RDIMMs) incorporate a register that buffers address and control
signals between the memory controller and the DRAM modules. This reduces electrical loading
on the memory bus, enabling more modules per channel and improving stability in high-
capacity server configurations. UDIMMs lack this buffering and are limited in capacity per
channel.
5. An organization is deploying a new virtualization host and needs to maximize memory
capacity while maintaining performance. The server supports both RDIMM and LRDIMM
modules. Which memory type should be selected for maximum capacity with acceptable
performance?
A) UDIMM
B) RDIMM
C) LRDIMM
D) ECC UDIMM
-” detailed answer 100 % correct :-”C
Rationale: Load-Reduced DIMMs (LRDIMMs) use advanced memory buffering that reduces
electrical loading even more than RDIMMs, allowing for the highest memory capacities per
, 4
channel (up to 256GB per module). While LRDIMMs have slightly higher latency than RDIMMs,
they offer the maximum capacity for memory-intensive virtualization workloads.
6. A network administrator is configuring a new switch and needs to implement port security
to prevent unauthorized devices from connecting. Which feature should be configured to limit
the number of MAC addresses that can be learned on a switch port and take action when the
limit is exceeded?
A) 802.1X authentication
B) Port security with sticky MAC addresses
C) VLAN access control lists
D) DHCP snooping
-” detailed answer 100 % correct :-”B
Rationale: Port security with sticky MAC addresses allows the administrator to specify the
maximum number of MAC addresses that can be learned on a port and define the violation
action (shutdown, restrict, or protect). This prevents unauthorized devices from connecting to
the network by limiting MAC address learning.
7. A server has six 1TB drives available. The administrator needs to configure RAID that
maximizes usable storage capacity while tolerating the failure of any two drives. Which RAID
level should be configured?
A) RAID 5
B) RAID 6
C) RAID 10
D) RAID 50
-” detailed answer 100 % correct :-”B
Rationale: RAID 6 uses dual parity, allowing the array to tolerate the failure of any two drives
simultaneously. With six 1TB drives, RAID 6 provides (6-2) × 1TB = 4TB of usable storage. RAID 5
only tolerates a single drive failure. RAID 10 with six drives would provide 3TB (three mirrored
pairs) but only tolerates one drive per mirror pair.
8. Which hardware component is responsible for translating virtual memory addresses to
physical memory addresses and is integrated into modern x86 processors?
CompTIA Secure
Infrastructure Specialist
(CSIS) – 150 Advanced
Practice Questions a well
detailed one 2025 /
2026 written and graded
A+ upgraded
Title: Comprehensive Advanced Practice Examination for the CompTIA Secure Infrastructure
Specialist (CSIS) Certification: 150 Mixed-Difficulty Multiple-Choice Questions Covering
Hardware, Networking, Security, Troubleshooting, and Infrastructure Protection Domains
, 2
Section 1: Hardware and Infrastructure Fundamentals (Questions 1–25)
1. A server administrator notices that a critical production server is experiencing intermittent
unexpected reboots. The system logs show no operating system errors or application crashes
prior to the reboots. Which hardware component is MOST likely the root cause?
A) Failing RAID controller battery
B) Overheating CPU due to thermal paste degradation
C) Failing power supply unit with voltage fluctuations
D) Corrupt BIOS firmware
-” detailed answer 100 % correct :-”C
Rationale: Intermittent unexpected reboots without OS or application errors are classic
symptoms of a failing power supply unit (PSU) that cannot maintain stable voltage delivery.
RAID controller battery failure typically causes cache data loss, not system reboots. CPU
overheating would generate thermal alerts in system logs. BIOS corruption would prevent
booting altogether.
2. Which RAID level provides the BEST balance of performance, capacity utilization, and fault
tolerance for a high-transaction database server with four identical disks?
A) RAID 0
B) RAID 1
C) RAID 5
D) RAID 10
-” detailed answer 100 % correct :-”D
Rationale: RAID 10 (RAID 1+0) provides both striping for performance and mirroring for fault
tolerance, offering the best balance for database workloads. It can sustain multiple disk failures
(one per mirror pair) and delivers excellent read/write performance. RAID 5 offers good capacity
utilization but has write performance penalties due to parity calculations.
3. A technician is troubleshooting a workstation that produces a series of beeps during POST
and fails to display anything on the monitor. The beep code pattern is three long beeps
followed by two short beeps. According to standard AMI BIOS beep codes, what does this
indicate?
A) Video card failure
B) Memory parity error
, 3
C) Keyboard controller failure
D) Base 64K memory failure
-” detailed answer 100 % correct :-”A
Rationale: AMI BIOS beep codes use specific patterns to indicate hardware failures. Three long
beeps followed by two short beeps typically indicates a video card failure or display adapter
issue. This is a common POST error that prevents the system from completing the boot process.
4. Which of the following memory module types is designed with a register between the
DRAM modules and the system's memory controller to reduce electrical loading and improve
stability in high-capacity configurations?
A) UDIMM
B) RDIMM
C) SODIMM
D) LRDIMM
-” detailed answer 100 % correct :-”B
Rationale: Registered DIMMs (RDIMMs) incorporate a register that buffers address and control
signals between the memory controller and the DRAM modules. This reduces electrical loading
on the memory bus, enabling more modules per channel and improving stability in high-
capacity server configurations. UDIMMs lack this buffering and are limited in capacity per
channel.
5. An organization is deploying a new virtualization host and needs to maximize memory
capacity while maintaining performance. The server supports both RDIMM and LRDIMM
modules. Which memory type should be selected for maximum capacity with acceptable
performance?
A) UDIMM
B) RDIMM
C) LRDIMM
D) ECC UDIMM
-” detailed answer 100 % correct :-”C
Rationale: Load-Reduced DIMMs (LRDIMMs) use advanced memory buffering that reduces
electrical loading even more than RDIMMs, allowing for the highest memory capacities per
, 4
channel (up to 256GB per module). While LRDIMMs have slightly higher latency than RDIMMs,
they offer the maximum capacity for memory-intensive virtualization workloads.
6. A network administrator is configuring a new switch and needs to implement port security
to prevent unauthorized devices from connecting. Which feature should be configured to limit
the number of MAC addresses that can be learned on a switch port and take action when the
limit is exceeded?
A) 802.1X authentication
B) Port security with sticky MAC addresses
C) VLAN access control lists
D) DHCP snooping
-” detailed answer 100 % correct :-”B
Rationale: Port security with sticky MAC addresses allows the administrator to specify the
maximum number of MAC addresses that can be learned on a port and define the violation
action (shutdown, restrict, or protect). This prevents unauthorized devices from connecting to
the network by limiting MAC address learning.
7. A server has six 1TB drives available. The administrator needs to configure RAID that
maximizes usable storage capacity while tolerating the failure of any two drives. Which RAID
level should be configured?
A) RAID 5
B) RAID 6
C) RAID 10
D) RAID 50
-” detailed answer 100 % correct :-”B
Rationale: RAID 6 uses dual parity, allowing the array to tolerate the failure of any two drives
simultaneously. With six 1TB drives, RAID 6 provides (6-2) × 1TB = 4TB of usable storage. RAID 5
only tolerates a single drive failure. RAID 10 with six drives would provide 3TB (three mirrored
pairs) but only tolerates one drive per mirror pair.
8. Which hardware component is responsible for translating virtual memory addresses to
physical memory addresses and is integrated into modern x86 processors?