Transcript Trouble Shooting

Trouble Shooting
• It’s Broken!
The BEST approach
Troubleshooting Tips
• Did the user back anything up?
– No: Oh Well…
– Yes: Proceed with troubleshooting
• Isolating the problem
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If it ain’t broke don’t fix it!
Communicate with the user
Is it hardware failure or improper use?
Is the problem local or regional?
TROUBLESHOOTING FLOWCHART
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* DON'T *
* DID YOU * NO
* FOOL
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* WITH IT! *
* WITH IT ? *
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* KNOW? *
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* WILL YOU
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Troubleshooting
• Start With a PLAN!
• Get the right amount of information
– not too much
– not enough
– Ask a lot of questions
• Analyze
– Familiarize yourself with the system’s software
and hardware
Troubleshooting
• Prioritize
– Network
• Local (fix it!)
• Wide Area (call someone to fix it!)
– Server
– User
• Collect the data
• Isolate the problem
Ridge Hall computer assistant; may I help you?"
"Yes, well, I'm having trouble with WordPerfect."
"What sort of trouble?"
"Well, I was just typing along, and, all of a sudden the words went away."
"Went away?"
"They disappeared"
"Hmm. So what does your screen look like now?"
"Nothing"
"Nothing?"
"It's blank; it won't accept anything when I type.
"Are you still in WordPerfect, or did you get out?"
"How do I tell?"
"Can you see the C:\ prompt on the screen?"
"What's a sea-prompt?"
"Never mind. Can you move the cursor around on the screen?"
"There isn't any cursor. I told you, it won't accept anything when I type."
"Does your monitor have a power indicator?"
"What's a monitor?"
"It's the thing with the screen on it that looks like a TV. Does it have a little light that tells you when it's on?"
"I don't know."
"Well, Then look on the back of the monitor and find where the power cord goes into it. Can you see that?"
......"Yes, I think so."
"Great! Follow the cord to the plug, and tell me if it's plugged into the wall."
......"Yes, it is."
"When you were behind the monitor, did you notice that there were two cables plugged into the back of it, not just one?"
"No"
"Well, there are. I need you to look back there again and find the other cable."
......"Okay, here it is."
"Follow it for me, and tell me if it's plugged securely into the back of your computer."
"I can't reach."
"Uh huh. Well, can you see if it is?"
"No."
"Even if you maybe put your knee on something and lean way over?"
"Oh, it's not because I don't have the right angle - it's because it's dark."
"Dark?"
"Yes, the office light is off and the only light I have is coming in from the window."
"Will, turn on the office light, then."
"I can't"
"No? Why not?"
"Because there's a power outage."
"A power... A power outage? Aha! Okay, we've got it licked now. Do you still have the boxes and manuals and packing stuff your
computer came in?"
"Well, yes, I keep them in the closet."
"Good! Go get them, and unplug your system and pack it up just like it was when you got it. Then take it back to the store you bought it
from."
"Really? Is it that bad?"
"Yes, I'm afraid it is."
"Well, all right then, I suppose. What do I tell them?"
"Tell them you're too stupid to own a computer."
More Jokes
A helicopter was flying around above Seattle when an electrical malfunction disabled all of the
aircraft's electronic navigation and communications equipment. Due to the clouds and haze, the
pilot could not determine the helicopter's position and course to steer to the airport. The pilot saw
a tall building, flew toward it, circled, drew a handwritten sign, and held it in the helicopter's
window.
The pilot's sign said "WHERE AM I?" in large letters. People in the tall building quickly
responded to the aircraft, drew a large sign, and held it in a building window. Their sign said
"YOU ARE IN A HELICOPTER." The pilot smiled, waved, looked at his map, determined
the course to steer to SEATAC airport, and landed safely. After they were on the ground, the
copilot asked the pilot how the "YOU ARE IN A HELICOPTER" sign helped determine their
position. The pilot responded "I knew that had to be the MICROSOFT building because they
gave me a technically correct, but completely useless answer."
Troubleshooting (cont)
• Tools
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Software (programs, sniffers)
Hardware (line analyzers) Techniques
Systematic search
Top down (start at keyboard, end at internet)
Use Deja Vu (I’ve seen this before)
• Wheel Spinning
• Jumping to Conclusions
Tools
• Cable Tester
– Continuity, length
• Flashlight (Fiber)
• Volt Meter (Digital or Analog)
– Voltages
– Resistances
• TDR
– Length and quality of cable.
More Troubleshooting
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Look for the obvious
Know when to ask for help
Know who to ask for help
Know what help to ask for
Give details of the problem
Try not to argue
Programs
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Traceroute
Ping
Winipcfg
Ipconfig
Netstat
Nbtstat
Telnet
Network Analysis
• Protocol Analyzers (Sniffer, TCPdump)
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Bottlenecks
Broadcast storms
Unusual Patterns
Trends of traffic
• Use Network Graphing Tools
Twisted Pair
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Proper category cable (cat 3 vs. cat 5)
Proper crimping of connections
Pinched or cut cables
Link light abnormalities
Is there an address conflict? (IP)
Twisted Pair Testing
• Continuity
– Volt/Ohm meter
– 10baseT/100baseT hub/adapter will act as a short
• Time Domain Reflectometry
– Simple network tester
• NEXT (Near End Cross Talk)
– Complex (Expensive) network tester
– B.E.R.T. (Bit Error Rate Tester)
Time Domain Reflectometry
• Utilizes the speed of light 300,000,000
meters per second slowed by the medium
being measured (velocity factor)
• Detector senses a reflection of the signal
• Timer measures the delay from incident
wave (transmitted pulse) and reflected wave
(received pulse)
Time Domain Reflectometry
Input Pulse
Splice
Signal
(DB)
End of cable (or break)
Time (Microseconds)
Fiber Installation
• Can be expensive but does solves some
distance problems
• Installation required specialized equipment
• Fibers are fragile
• Fiber is not susceptible to electrical
disturbances
• Fiber is secure (not easy to tap)
• Somewhat easy to test
More Fiber Installation
• Single mode goes longer distances than
multi mode but media is more expensive
• Needs careful optical alignment
• Individual fibers are fragile
• Each splice/connector increases line loss
• Transmit and receive on separate fibers
Review
• Network Protocols
– TCP/IP
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Layers
Sockets, Ports, handshake
TCP
UDP
ICMP
– IPX
– Netbios, Netbeui, SMB
– Appletalk
More Review
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Modem systems (PPP protocol)
Line terminology (T1, DS3, X.25)
Serial Communications, synchronous and asynchronous
ISDN and DSL lines
Designing a client/server system including networking.
Network Security
– Physical
– Data
• Fault Tolerance
• Backup, Disaster Preparation, Disaster Recovery
And More Review
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Adding Users and Shares
Printing on the network
SMTP, POP, and IMAP mail systems
HTTP and the WEB
Traceroute
I hope it’s fixed!!!
The End