( (5) CORE 1) FINALLL CompTIA A+ 220-1101 Study Guide

How to troubleshoot

(5.1)

• Uh oh… It’s broken!

• Identify the problem

• Establish a theory… Sometimes the simplest problem is the problem.

• Test the theory.

(5.2)

Troubleshooting Common Hardware Problems

POST and boot

• Blank screen on boot

  • Listen for beeps

  • Bad video, bad ram, bad CPU

  • BIOS configuration issue

BIOS time and setting

• Maintained with the motherboard battery

• Replace the battery

Crash screens

Bluescreens and spontaneous shutdowns

Startup and shutdown BSOD

• Bad hardware, bad drivers, bad application

Use last known Good, System Restore, or Rollback Driver

• Try Safe Mode

Reseat or remove the hardware

• If possible

Black Screen

• Is the monitor connected?

• Input selection?

(5.3)

3rd party risk

3rd party business partners share important data
- Perform risk assessment

(5.3)

(5.3)

Rules of engagement

Defines purpose and scope of pen test

Rules of test
- ip address ranges
- in/out of scope apps and devices
etc

Time, internal/external, etc.

(5.3)

(5.3)

Vendor selection process

Due diligence
- check vendors to make sure they are legit

Conflict of interest
- can compromise judgement

(5.3)

(5.3)

Ongoing management of vendor relationship

Reviews should be on regular basis
- Financial, IT security, etc.

(5.3)

(5.3)

Right to audit clauses

Legal agreement to have the option to perform security audits at any time
- in contracts with 3rd parties
- verify security

(5.4 Troubleshooting Video & Display Issues)

No video image?

• Is it connected?

• Right input?

Dead pixels?

• Black spot. Defect.

Flashing screen?

• Replace video cable.

• Switch display.

• Confirm the display matches with the system.

Incorrect color display?

• Check colors

• Display options

• Tint

• OS configurations like night light.

Audio issues?

• Speakers on monitor? No sound or low volume.

• Check audio controls.

• Confirm audio input.

• Check for audio jacks.

Dim image?

• Brightness

• Contrast

• Maybe OS? Auto dimming, dim on battery, power saving.

• Backlight failure. Some or all.

LCD Projector troubleshooting…

• No light output

• Cooling issue as fans constantly cool the bulb. Shuts down if temperatures are high.

Check airflow.

• Remove any blockages. Clean dust from air filters and external air input/output.

(5.5 Troubleshooting Mobile Devices)

Poor battery health?

• Replace the aging battery

• Only so many recharges

Bad reception?

• Should turn on airplane mode.

• Avoid the always searching for signal.

And disable unnecessary features

• 802.11 wireless, bluetooth, GPS.

Swollen battery?

Broken screen?

Improper charging?

• Check for cables, interfaces, and obstructions.

• Don't use frayed cables. And try from a known good cable.

Poor or no connectivity

Cellular or wifi?

• location, location, location

Signal strength?

• Outdoors may be better

Wifi?

• Interfereence can limit.

• May need channel/frequency configuration change.

Liquid damage?

• Most phones have liquid contact indicator (LCI)

• Turne color when liquid is present.

• You should power down the phone. And perhaps put it in silicia gel, NOT a bag of rice.

(5.6 Troubleshooting Printers)

• Print or scan a test page

• Built into Windows

Faded prints or blank pages?

• Low toner or ink.

Lines down printed page?

• Inkjet: Clean print heads.

• Laser: Check for wcratched photosensitive drum.

Double/echo images or speckling

• Laser printer optical drum not cleaned properly.

• Ghost or “shadow” rom previous drum rotation

Garbled print?

• Bad driver or model. PCL or Postscript.

• Bad application. Check output and/or upgrade. Verify printer functionality.

Toner not sticking to the paper?

• Smudges?

• Toner not fused? May not be hot and it should be permanently melted and pressed.

• Fuser problem? Replace it.

Multiple prints pending in queue

• Corrupted print jobs.

• Print spooler crash, spooler configuration restart.

• You should monitor the queue for details.

Incorrect page orientation?

• Check settings.

• May require driver update.

(5.7 Troubleshooting networks)

Do you have a link light?

• Is it plugged in?

Ping Loopback (127.0.0.1)

Ping local IP address

• Check the local configuration, adapter, and link signal.

Ping default gateway

Ping devices on router

• 8.8.8.8 or 9.9.9.9

Intermittent wireless connectivity

Interferance.

Signal strength. Transmitting attenna or signal, receiving antenna. Etc.

Incorrect channel. Usually automatic. Look for manuel.

Wireless interference?

• Microwave oven, fluorescent lights.

• Multi tenant building??? Unpredictable.

Measurements?

• Signal to noise ratio (SNR)

• Performance monitor

Jitter?

• Data should arrive at regular intervals. Miss a packet? Lose communication. Jitter = Time between frames.

Latency?

• Delay between request and response. Packet captures can provide detailed analysis. Check it along the way.

Port flapping?

Network interface go up and down? Verify cable. Move between switch interfaces. Replace bad hardware.