1. © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public ITE PC v4.0 Chapter 1 1 Troubleshooting Your Network Networking for Home and Small Businesses – Chapter 9

2. ITE PC v4.0 Chapter 1 2 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Chances are good that you have used a help desk  Telephone  "live chat" option over the Internet. Still others use a combination of these  Some are free  Some companies charge for assistance.

3. ITE PC v4.0 Chapter 1 3 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Why do people call?  Can you guess the number one reason why people call help desks?  http://www.itnews.com.au/News/NewsStory.aspx?story =46929 http://www.itnews.com.au/News/NewsStory.aspx?story =46929 Forgotten passwords are 20% of the calls made annually to help desks Hardware failures comprise about 16% of the calls Remote access issues account for 12% Email 11% of all calls

4. ITE PC v4.0 Chapter 1 4 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Our Tickets

5. ITE PC v4.0 Chapter 1 5 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public The Troubleshooting Process  Most people rely on instinct to help troubleshoot  Important to maintain documentation to help in the process – record problems encountered – what steps were taken to determine the cause – what steps have been taken to make sure it doesn’t occur again.

6. ITE PC v4.0 Chapter 1 6 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public The Troubleshooting Process  Step 1 – Gather information – Question the individual who has the problem end user experiences observation by the user error messages  Step 2 – Collect information about affected equipment – look at log files – changes – warranty information – network monitoring tools used for larger networks

7. ITE PC v4.0 Chapter 1 7 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Troubleshooting Techniques  Use OSI layered approach  Top-down – start at application layer – work down until faulty error occurs  Bottom-up – start at physical layer and work up – hardware, cabling, etc problems – more complex  Divide and Conquer – begins in the middle layers – based on experience

8. ITE PC v4.0 Chapter 1 8 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public The Cable Guy  http://technet.microsoft.com/en-us/library/bb878072.aspx The Microsoft Cable Guy writes that "A network administrator must know how to methodically analyze a TCP/IP-related networking problem in terms of the various layers of the TCP/IP model and use the appropriate tools to be effective in isolating and resolving issues with successful communication on an TCP/IP network."

9. ITE PC v4.0 Chapter 1 9 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Approaches to Troubleshooting  Trial and Error – relies on an individual’s knowledge – educated guess based on past experiences – if it doesn’t work, try, try again  Substitution – problem assumed to be caused by a specific part – the solution – replace the part – used for inexpensive items cables, etc

10. ITE PC v4.0 Chapter 1 10 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Utilities Used to Detect Physical Problems  Use your senses  Sight  Smell  Touch  Hearing

11. ITE PC v4.0 Chapter 1 11 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Utilities Used to Verify TCP/IP Connectivity  Use CLI  IP Config – checks to make sure correct IP, subnet mask and DNS server  Ping – verifies connectivity to other hosts  Tracert – traces the route of the packet  Netstat – show what networks / ports are active  Nslookup – asks the name server for ip information

12. ITE PC v4.0 Chapter 1 12 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public IP CONFIG commands  Ipconfig - displays current IP configuration – IP address – Subnet Mask – Default Gateway  Ipconfig /all – displays additional information – DHCP – DNS information  Ipconfig /release – used with DHCP – release IP address  Ipconfig /renew – used with DHCP – refreshes IP

13. ITE PC v4.0 Chapter 1 13 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public The Ping Command  Used to determine whether or not the host is reachable  Can be used with either an IP address of name of destination  Echo request – ping sent  Echo reply – destination host responds  Ping issues – able to ping both IP and name, but unable to access application problem likely at destination host –Unable to ping both IP and name network connectivity problem if able to ping default gateway, problem not at local level

14. ITE PC v4.0 Chapter 1 14 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public The Tracert Command  Shows each hop along the way  Tells how long it takes for the packet to be sent and get a response (round trip time)  30 hops – network/user deemed unreachable – default settings – can be changed

15. ITE PC v4.0 Chapter 1 15 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public The Netstat Command  Views open connections on a host  Informs user about: – protocols – local address – port numbers – connection state

16. ITE PC v4.0 Chapter 1 16 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public The Nslookup Command  Allows end user to look up information about DNS name and DNS server  Used as a troubleshooting tool to see if DNS server has the correct IP with the correct name

17. ITE PC v4.0 Chapter 1 17 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Hardware and Connection Issues in Wired & Wireless Networks  Use divide-and-conquer technique  To determine where the problem exists: – ping from wireless client to default gateway – ping from wired client to default gateway – ping wireless client to wired client

18. ITE PC v4.0 Chapter 1 18 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public LED Indicators  Used to show activity  Security LED – solid green = security enabled  Link Lights – solid green = plugged in with no traffic – flashing green = plugged in with traffic – amber = making adjustments  Power LED – solid green = operational

19. ITE PC v4.0 Chapter 1 19 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Discussion  You have a mixed hard wired and wireless network in your home, 2 clients that have no connectivity with an Integrated Router and you haven't yet isolated the problem.  Think about the four approaches we studied in the last lesson. Which one might you use to solve a problem such as this?" Now… How might you troubleshoot this problem?"

20. ITE PC v4.0 Chapter 1 20 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Discussion

21. ITE PC v4.0 Chapter 1 21 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Cable Issues  One of the most common problems  Check for: – correct cable type – improper cable termination – too long of cable runs – verify correct ports – protect cables from damage

22. ITE PC v4.0 Chapter 1 22 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Radio Problems with a Wireless Network  What if... – the wireless client is unable to connect to the access point  Possible fixes: – check wireless standards being used – check channels – check signal strength may be too far away from AP – check for outside interference – check available bandwidth too many clients on one channel

23. ITE PC v4.0 Chapter 1 23 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Association and Authentication Issues  SSID – make sure client is configured with the correct SSID  Check Authentication – open (by default) – might have be changed check to make sure the correct key is being used  Encryption – key needed by the client

24. ITE PC v4.0 Chapter 1 24 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Discussion  Complete the row labeled “Association and Authentication Problems on a WAN”

25. ITE PC v4.0 Chapter 1 25 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public DHCP Problems  Make sure the IP address of the client is on the same network as the ISR  If both client and access point are not on the same network, use release and renew

26. ITE PC v4.0 Chapter 1 26 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public ISR Router to the ISP Problems  Wired and Wireless devices can connect to each other, but not the Internet... Why??  May be a connection between the access point and the ISP – check out the router status page – check physical connections (including indicator lights) – verify passwords – may be that the Internet site is just down

27. ITE PC v4.0 Chapter 1 27 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Reflection: Expanding the Troubleshooting Table  http://www.microsoft.com/technet/prodtechnol/winxp pro/maintain/wlansupp.mspx can be used to expand the troubleshooting table created in class. http://www.microsoft.com/technet/prodtechnol/winxp pro/maintain/wlansupp.mspx 1.Read the article, paying careful attention to Table 1 and Appendix A, "Wireless connections and solutions". 2.Compare and contrast the solutions offered in Table 1 and Appendix A, to your troubleshooting table, identifying "new" solutions to network connectivity problems. 3.Add these solutions to the troubleshooting table. 4.Be prepared to share these solutions with the class.

28. ITE PC v4.0 Chapter 1 28 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Documentation  Set a performance baseline – do this just after the network is installed and running efficiently  When documenting a problem, include the following – initial problem – steps taken – result of the steps – determined cause of problem – how the problem was resolved – preventive measures taken

29. ITE PC v4.0 Chapter 1 29 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Discussion  What do you do when your knowledge of troubleshooting a problem with your phone, video game, or computers isn’t enough to solve the problem?  How many of you have ever used a help desk?  What type of help desk services have you used? You are going to learn the types of information that help desks and other external resources will need to help troubleshoot difficult connectivity problems.

30. ITE PC v4.0 Chapter 1 30 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Using the Helpdesk  Provides assistance for the end user to help fix a problem – via email – via live chat – via phone  Use of remote access – help desk takes control of your machine  Inform the help desk of the following: – symptoms – who had the problem – when it happened – steps taken – results of steps taken

31. ITE PC v4.0 Chapter 1 31 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Discussion  What type of information is required by the help desk to troubleshoot the problem? 1.Symptoms encountered 2.Who encountered the problem 3.When the problem manifests 4.Steps taken to identify the problem 5.Results of steps taken 6.Date and time of previous call (if any) Trouble ticket number Name of technician

32. ITE PC v4.0 Chapter 1 32 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Discussion  What type of information do you need to document when calling a help desk? 1.Time/date of call 2.Name/ID of technician 3.Problem reported 4.Course of action taken 5.Resolution/Escalation 6.Next steps (follow-up) if required

33. ITE PC v4.0 Chapter 1 33 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Reflection: Help Desk Resources  In this activity, you will research available help desk resources for a cell phone, an Mp3 player, a video game system, a personal computer, and an ISR. Begin by selecting a cell phone, Mp3 player, video game system, personal computer, and an ISR about which you will research available help desk resources. Use an Internet Search Engine to identify the customer support pages for each of these devices. Document the telephone number for accessing the help desk Document the availability of email support - what is the address and promised response time? Document the availability of "Live online chat." Is this service offered? During what hours is this service available to a user? Document the availability of user forums, FAQ’s, and documentation.

34. ITE PC v4.0 Chapter 1 34 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public  Is there a charge for troubleshooting? How much is the charge? Thinking about the available resources, when might you call the help desk for a solution? When is live chat a good option? What about the use of email support? Be prepared to discuss your responses with the class.  Divide the class into teams, having each team present the results of the troubleshooting process back to the whole class.

35. ITE PC v4.0 Chapter 1 35 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public Summary  Effective troubleshooting combines instinct, experience, and structured techniques to identify, locate, and correct network or computer problems.  Documentation is essential in effective troubleshooting, and should contain baseline information about the network.  A large proportion of networking problems relate to physical components.  Many networking problems can be identified with software utilities such as ping, tracert, and netstat.  In a network containing both wired and wireless connections, it is important to isolate the problem to either the wired or wireless network.

36. ITE PC v4.0 Chapter 1 36 © 2007 Cisco Systems, Inc. All rights reserved.Cisco Public