SK0-005 troubleshooting Practice Test 4 — 15 Questions

Question 1

A web application server is experiencing intermittent 502 Bad Gateway errors during peak usage hours. The server's reverse proxy logs show connections to the backend application server being refused. The application server's resource monitor shows CPU utilization at 95% and memory utilization at 40%. Which of the following actions is MOST likely to resolve the issue?

Accepted Answer

Adjust thread pool and connection timeout settings on the application server.. Option B is correct. High CPU and connection refusals commonly indicate that the application’s worker thread pool or connection queue is saturated, preventing new connections. Tuning thread pool and timeout settings can alleviate this. Adding CPU (option C) may help long-term but is not the most direct fix. Memory (option A) is not the bottleneck. Replacing the proxy (option D) does not address the backend overload.

Answer

Replace the reverse proxy with a hardware load balancer.

Answer

Add more CPU cores to the server.

Answer

Increase the server's physical memory.

Question 2

After a thunderstorm, a server in a remote office is reachable via remote console but has no network connectivity. The network switch port shows a steady link light, but the server's NIC shows no link light. Which of the following is the MOST likely cause?

Accepted Answer

The NIC hardware has failed.. Option C is correct. A lack of link light on the server's NIC while the switch has a link indicates a physical failure between the NIC and the cable, such as a damaged NIC. Option A would result in no link on the switch as well. Option B would still allow the NIC to establish link. Option D would not affect link lights.

Answer

TCP/IP stack corruption.

Answer

Switch port is administratively disabled.

Answer

Incorrect VLAN assignment on the switch port.

Question 3

A server fails to complete POST and emits a series of beeps: two long, three short. According to the manufacturer's documentation, this beep code indicates a memory error. The server has eight DIMMs installed. Which of the following steps should the technician perform FIRST?

Accepted Answer

Reseat all memory modules and attempt to boot.. Option A is correct. Reseating memory modules is the least invasive and often the most effective first step for beep codes indicating memory errors, as poor connections from thermal expansion or vibration can cause such issues. Option B is excessive before attempting reseating. Option C may reset BIOS settings but does not physically reseat RAM. Option D does not directly address the immediate memory detection failure.

Answer

Replace all memory modules.

Answer

Clear the CMOS battery.

Answer

Update the server's UEFI firmware.

Question 4

A server experienced an unexpected power loss. After power is restored, the server boots successfully, but several critical services fail to start automatically. The administrator checks the system logs and finds errors indicating missing LUNs from a SAN. The SAN administrator confirms the SAN is online and the LUNs are assigned to the server's WWNs. The server uses FC HBAs. Which TWO steps should the administrator perform to diagnose the issue?

Accepted Answer

Rescan the SCSI bus on the server.. Options A and C are correct. After an unexpected power loss, the SAN topology or host's view of LUNs may be stale. Rescanning the SCSI bus forces the host to re-discover all accessible LUNs. Checking FC switch zoning ensures that the path between the host and storage is still correctly allowed after the power event. Option B is unnecessary and disruptive, as the SAN is confirmed online. Option D is premature. Option E is unrelated to sudden LUN disappearance after power restoration.

Answer

Replace the FC HBAs.

Answer

Reboot the SAN controller.

Answer

Reinstall the multipathing driver.

Question 5

Refer to the exhibit. A Linux server started reporting I/O errors to its local disk. The administrator runs `dmesg` and sees the output shown. Which of the following is the MOST likely cause of the errors?

Accepted Answer

The disk has a bad sector that cannot be remapped.. Option B is correct. The 'Medium Error' sense key along with 'Unrecovered read error - auto reallocate failed' indicates a physical bad sector that the drive could not reallocate. Option A would typically produce a different hostbyte (e.g., DID_NO_CONNECT). Option C, outdated firmware, rarely causes medium errors. Option D, filesystem corruption, would manifest as filesystem-level errors, not SCSI sense codes.

Answer

The filesystem on /dev/sda is corrupted.

Answer

The SCSI cable is loose.

Answer

The RAID controller firmware is outdated.

Question 6

Refer to the exhibit. A Windows file server at a branch office lost network connectivity after a scheduled reboot. The administrator logs in via the console and runs `ipconfig /all`, which shows the output in the exhibit. The server should have a static IP of 10.0.0.50. What should the administrator do to restore connectivity?

Accepted Answer

Set a static IP configuration as intended.. Option A is correct. The exhibit shows an APIPA address (169.254.x.x), which indicates the server obtained an automatic private address because it could not reach a DHCP server. However, since the server is supposed to use a static IP, the administrator should directly configure the static IP settings. Option B would fail because no DHCP server is reachable. Option C is true but not the correct solution for a server that needs a static IP. Option D is unrelated to the IPv4 configuration issue.

Answer

Disable IPv6 on the network adapter.

Answer

The DHCP server is unreachable; check DHCP server availability.

Answer

Release and renew the DHCP lease.

Question 7

A company uses a two-node failover cluster for a critical database application. The cluster consists of Node A and Node B, with shared storage connected via SAS. During a routine check, the administrator discovers that Node A has failed and the cluster resources did not fail over to Node B. The cluster service is running on Node B, but the database resource remains offline. Node B can successfully ping Node A's management IP address but not the dedicated cluster heartbeat IP. The shared storage appears in the operating system on Node B, but attempts to bring the disks online fail. The administrator must restore database service as quickly as possible. Which of the following actions should the administrator take FIRST?

Accepted Answer

Check and repair connectivity to the shared storage from Node B. The immediate problem is that the database resource cannot start because the shared storage cannot be brought online. This indicates a storage connectivity issue (e.g., SAS cable, HBA, or multipath problem) that must be resolved before any cluster actions can succeed. Rebooting Node A (A) might restore the node but takes time and may not fix the storage access for Node B. Running the cluster validation wizard (B) is a diagnostic step, not a repair action, and would delay service restoration. Forcing quorum on Node B (C) allows cluster operations but does not address the underlying storage problem; the disk would still fail to come online.

Answer

Run the cluster validation wizard

Answer

Force a quorum on Node B using the /forcequorum switch

Answer

Reboot Node A

Question 8

A server administrator notices that a recently installed PCIe network card is not being recognized by the operating system. The server is running Windows Server 2019. The administrator has verified that the card is securely seated and that the slot is enabled in the BIOS. Which of the following should the administrator try FIRST to resolve the issue?

Accepted Answer

Check the Hardware Compatibility List (HCL) for Windows Server 2019.. Option B is correct because the first step when a newly installed device is not recognized should be to verify hardware compatibility with the operating system (checking the Hardware Compatibility List). This ensures the device has supported drivers. Options A and C are physical steps that have already been considered (secure seating, slot enabled), and D (updating BIOS) is a later step after confirming compatibility.

Answer

Replace the network card with a known-good card.

Answer

Reseat the network card in a different PCIe slot.

Answer

Update the server BIOS to the latest version.

Question 9

A database server running on a Linux VM has started experiencing periodic crashes. The VM is hosted on an ESXi hypervisor. The system logs show entries: 'kernel: Out of memory: Kill process 12345 (mysqld) score 700 or sacrifice child'. The VM has 16GB RAM allocated and no memory overcommitment on the host. The DBA reports that the database workload hasn't increased. Which of the following actions should be taken FIRST to diagnose the issue?

Accepted Answer

Check the host's memory utilization for ballooning or swapping.. Option C is correct because the OOM killer being invoked in a VM with stable workload suggests possible host-level memory constraints (e.g., ballooning, swapping) affecting the VM. Checking the host's memory utilization helps confirm whether the hypervisor is under memory pressure and causing the VM to think it's out of memory. Options A and D are configuration changes that might alleviate symptoms but don't diagnose root cause. B addresses database tuning, which is not indicated when the system reports OOM.

Answer

Add a memory reservation for the VM in ESXi.

Answer

Analyze the database query cache hit ratio and slow query logs.

Answer

Increase the VM's RAM allocation to 32GB.

Question 10

A server technician has just replaced a failed hard drive in a RAID 5 array. After inserting the new drive, the array begins rebuilding, but after 10 minutes, the rebuild fails and the array status shows 'degraded' again. Which of the following is the MOST likely cause?

Accepted Answer

The new drive is larger than the other drives in the array.. Option A is correct. In RAID 5, if the replacement drive is larger than the other drives, some RAID controllers will fail the rebuild because they cannot utilize the extra capacity or may encounter metadata inconsistencies. Option B is unlikely because enterprise drives are typically hot-swappable. Option C (firmware differences) can sometimes cause issues but is less common than size mismatch. Option D (rotational speed) rarely prevents a rebuild.

Answer

The new drive has a higher rotational speed.

Answer

The new drive has a different firmware version than the other drives.

Answer

The new drive is not hot-swappable and was inserted while the server was on.

Question 11

A server administrator is troubleshooting a network connectivity issue where a newly installed server cannot communicate with other devices on the same subnet. The server has a static IP address configured. Other devices on the same switch can communicate. Which TWO of the following could be the cause of the issue? (Select TWO)

Accepted Answer

The switch port is configured with port security and has learned a different MAC address.. Options A and B are correct. An incorrect subnet mask (A) would cause the server to misinterpret which IPs are local, preventing communication with devices on the same subnet. Port security on the switch (B) could block traffic if the learned MAC address does not match. Option C (default gateway) is irrelevant for same-subnet communication. Option D (DNS) affects name resolution, not basic IP connectivity. Option E (DHCP) is not used since the server has a static IP.

Answer

The DNS server address is incorrect.

Answer

The server's default gateway is incorrectly set.

Answer

The DHCP server has exhausted its scope.

Question 12

A company has a small virtualized environment with two ESXi 7.0 hosts (HostA and HostB) managed by vCenter Server. They use a shared iSCSI storage array for all VMs. The network consists of a single physical switch that connects the hosts, storage, and management traffic using VLANs. Yesterday, the switch failed and was replaced with an identical model. After restoring the configuration from a backup, all VMs on HostA are working normally, but all VMs on HostB show 'network disconnected' in the vSphere console. The VMs on HostB are still running, but they cannot communicate with any other device on the network. HostB itself is reachable via its management IP and can access the storage array. The administrator has verified that the physical cables are correct and the NICs are up on HostB. The VLAN configuration on the new switch was restored for the ports connecting HostB, but the issue persists. Which of the following actions should the administrator perform FIRST to restore connectivity?

Accepted Answer

Check the VLAN configuration on the switch ports connected to HostB for the VM network uplinks.. Option B is correct. Since all other functions (management, storage) work and only VM traffic is affected, the most likely cause is incorrect VLAN tagging on the switch port carrying the VM traffic uplink. Restoring a switch config may have missed the exact VLAN trunk settings. Checking and correcting the VLAN configuration on the switch ports for HostB's VM network is the first targeted step. Options A and C are nondisruptive but don't address the immediate config issue. Option D involves rebooting the host without diagnosing, which is risky and may not fix the issue.

Answer

Reboot HostB to renegotiate the network configuration.

Answer

Restart the vCenter Server service on the vCenter appliance.

Answer

vMotion all affected VMs from HostB to HostA to confirm they work on HostA.

Question 13

A small business relies on a single Dell PowerEdge T340 tower server running Windows Server 2019 as its primary domain controller and file server. The server is situated in a locked, air-conditioned IT closet and is protected by an online surge protector. During a severe thunderstorm last evening, the building experienced a momentary power loss. This morning, the administrator found the server completely powered off. When the power button is pressed, the front panel diagnostic LEDs briefly illuminate, and all internal cooling fans start spinning for about two to three seconds, but then the server abruptly powers down. There are no audible beep codes, and the monitor never receives a video signal. The administrator has already verified the power cable is firmly seated in both the server and the surge protector, swapped the power cable with a known-good one, and tested the surge protector with another device, which powered on normally. No spare parts are immediately available, and server downtime must be kept to a minimum. What should the administrator do FIRST to diagnose and resolve the problem?

Accepted Answer

Replace the power supply with a compatible, known-good unit.. Option B is correct: the brief fan spin with immediate shutdown and absence of POST is a classic sign of a failing power supply that cannot maintain output under load. After a power surge, the power supply is the most probable damaged component. Option A is wrong because motherboard failure would typically produce beep codes or consistent power without POST, and swapping it is high-effort without first testing the power supply. Option C is wrong because RAM issues usually generate beep codes or a continuous power-on state with no boot, not the described brief spin-down. Option D is wrong because the administrator already confirmed other devices work on the same circuit, ruling out a supply-side issue.

Answer

Swap the motherboard with an identical one from a spare parts inventory.

Answer

Connect the server directly to a different power outlet, bypassing the surge protector.

Answer

Remove the server's RAM modules and reinstall them one at a time, testing after each.

Question 14

A medium-size enterprise runs a vSphere 7.0 cluster with two hosts (HostA and HostB) for production VMs. Each host has two 10GbE uplinks (vmnic0 and vmnic1) connected to separate physical switches (SW1 and SW2) for redundancy. A single vSphere standard switch (vSwitch0) uses both uplinks with teaming policy set to 'Route based on originating virtual port ID,' 'Network failure detection: Link status only,' and 'Notify switches: Yes.' Lately, several VMs running on HostA experience intermittent network disconnections lasting 20–30 seconds, while VMs on HostB are unaffected. The administrator checks vCenter events and sees repeated messages: 'Lost uplink redundancy on vSwitch0. vmnic0 is down.' followed seconds later by 'Uplink redundancy restored. vmnic0 is up.' The physical switch SW1's log shows the port for vmnic0 transitions through spanning-tree listening and learning states each time this occurs, taking about 15 seconds. The link is a trunk allowing all necessary VLANs, with no errors or security violations. The network team has already swapped the fiber cable and SFP+ transceiver for vmnic0 without improvement. The VMs affected are those whose virtual ports are pinned to vmnic0 by the load-balancing policy; VMs pinned to vmnic1 never experience disconnections. The administrator has also rebooted HostA and updated the NIC firmware, but the flapping continues. What should the administrator do to permanently resolve the intermittent connectivity?

Accepted Answer

Enable spanning-tree PortFast on the SW1 and SW2 ports connected to the hosts so the ports bypass the listening/learning states.. Option C is correct because the symptoms as confirmed by the switch log show that each link flap triggers spanning-tree recalculation, causing the port to cycle through listening and learning states before forwarding resumes. Enabling PortFast on switch ports that are connected to end devices (like ESXi hosts) allows immediate forwarding. Option A is wrong because changing to access mode would break multiple VLANs and still face STP delays. Option B is wrong because disabling notify switches might worsen MAC table inconsistencies. Option D is wrong because changing load balancing does not stop the flapping or STP convergence; the issue is at layer 2.

Answer

Disable the 'Notify switches' option on the vSwitch teaming configuration to avoid unnecessary RARP broadcasts.

Answer

Reconfigure the physical switch port for vmnic0 to an access port instead of a trunk to simplify spanning-tree operations.

Answer

Change the NIC teaming load balancing policy to 'Route based on IP hash' to distribute traffic across both uplinks more evenly.

Question 15

A file server running Windows Server 2016 is critical for a department's daily operations. For the past two weeks, it has been crashing with a blue screen every 1–2 days. The IT team collects minidump files and opens the latest one in WinDbg. After running '!analyze -v', they obtain the following output:
```
DRIVER_IRQL_NOT_LESS_OR_EQUAL (d1)
An attempt was made to access a pageable (or completely invalid) address at an interrupt request level (IRQL) that is too high. This is usually caused by drivers using improper addresses.
Arguments:
Arg1: fffff80012345678, memory referenced
Arg2: 0000000000000002, IRQL
Arg3: 0000000000000000, value 0 = read operation, 1 = write operation
Arg4: fffff80abcde1234, address which referenced memory
Debugging Details:
...
PROCESS_NAME:  fileserver.exe
SYMBOL_NAME:  NetAdapterCx.sys!NetAdapterCxSetLinkState+0x1234
IMAGE_NAME:  NetAdapterCx.sys
...
```
The server has 64GB ECC RAM, two Intel Xeon processors, and a Broadcom NetXtreme quad-port 10GbE NIC. The NIC driver was updated from version 7.12.6 to 7.14.8 two weeks ago as part of patch management. The BSODs started occurring immediately after that driver update; prior to the update, the server had been stable for over six months. The driver was obtained from the server manufacturer's support site and installed without error. The administrator wants to restore stability with minimal downtime and risk. Which action should the administrator take FIRST?

Accepted Answer

Boot into Safe Mode and roll back the network adapter driver to the previous version (7.12.6).. Option A is correct because the crash dump explicitly denotes NetAdapterCx.sys (the network driver framework) as the cause, and the problem started right after the driver was updated. Rolling back is the quickest and safest step to restore operational stability. Option B is wrong because an OS reinstall is extreme and unlikely to fix a driver-specific issue. Option C is wrong because the dump identifies a driver, not a memory fault, and ECC memory typically reports errors before causing crashes. Option D is wrong because a hardware replacement is costly and unnecessary when a driver rollback is available.

Answer

Replace the Broadcom NIC with a different brand network adapter and disable the onboard NIC in the BIOS.

Answer

Reinstall Windows Server 2016 and restore data from backups to eliminate any corrupted system files.

Answer

Run Windows Memory Diagnostic overnight to check for hardware memory errors that might corrupt driver loading.