TESTING AND TROUBLESHOOTING NETWORK tutorial

                         TESTING AND

TROUBLESHOOTING NETWORK

Network troubleshooting tools:-

• The various tools available for checking the networking are…….

1. Software Tools
2. Hardware Tools
3. Touchy Tools

                 LOOPBACK TEAST

• Signal is transmitted and it echos back.
• Echo signal compared with original signal.
• Tests are transmission pathand tools used for transmission.
• Traces a faulty node in network.
• Required a loopback plug.

                  NETWORK MONITOR

• Detect and display problems present in the netwirk.
• Provides data related to network traffic.
• Analyze data traffic to determine various network problems that can occur.

                      LAN TESTER - |

1. Used to test 10, 100 and 1000 base - T network.
2. Consists of two units.

• MAIN UNIT….

1. Indicate LAN device type is i.e. HUB, SWITCH.
2. Determine speed of LAN and type of link.

• REMOTE PROBE……

Used to locate faults in cable.

                     LAN TESTER - ||

• Functions of LAN tester……

1. Verify PC to Hub speed and data transmission.
2. Check Hub to Hub data transmission.
3. Determines any speed bottlenecks present on 10 and 100 Base-T LANs.
4. Continuously tracks LAN link.

   CABLE TEATER AND CERTIFIRES

• Checks electrical connections.
• Determines if a short or open circuit is present in the network.
• Consists of a source of current, volt meter and microcontroller.

   

TIME DOMAIN REFLECTOMETERS

• Locates fault in metallic cables.
• Transmits a pulse through the cable.
• At every discontinuity an echo is reflected back.
• Used to test long cable.
• Results are displayed on a CRT or LED.

           PROTOCOL ANALYZERS - |

• It may be a software or hardware device.
• Captures packets from network.
• Analyzes captures packets.
• Analyzes the network traffic.
• Identifies bottlenecks in network.
• Operate on NETWIRK LAYER.
• Identifies active system on network.
• Removes the faulty system from network.

               PROTOCOL ANALYZERS -||

Types of protocol analyzers…..

• Packet analyzer…….

1. Captures packets present on the wire and store the, for analyzing later.
2. Does a statistical analysis of the data captured but it is not its primary function.

• Statistical analyzers…..

1. Gather quantitative data to prepare a report on the different statistical trends.
2. Does not store the packets for later analysis.

                          TOUCHY TOOLS

• Used to identify network problem.
• Problems are identified using asking various questions to user.
• Analyzes current situation and compared it with set of baselines.
• Adequate knowledge and experience is useful to determine problems.

                          BACKUPS

• Used to preserves a copy of original files.
• Should be performed on regular basis.
• Useful when a data loss occurs.
• Restores system to previous state.

     TROUBLESHOOTING MODEL - |

steps of troubleshooting model…..

• Establish the symptoms.
• Isolate the cause of the problem.
• Establish what has changed that might have caused the problem.
• Ask isolating questions.

  TROUBLESHOOTING MODEL - ||

• Identify the most probable cause.
• Implement a solution.
• Test the situation.
• Recognize the potential effects of the solution.
• Document the solution.

                              SNMP

• Simple network management protocol.
• Networking standard protocol.
• Used with TCP/IP networks.
• Monitors and manage the networks.
• Helps to examine network performance.
• Detect network faults or inappropriate access.

Potential network connectivity problem…….

• Causes of network connectivity problem--

1. Incorrect network adapter(NIC).
2. Incorrect switch settings.
3. Faulty hardware.
4. Driver issues.
5. Upgradation of operating system.
6. Server relocation.
7. The network adapter is incompatible with the motherboard.

               NETSTART COMMAND

• Displays TCP/IP information.
• Determines which ports are active.
• Identifies ports that are vulnerable to attacks.
• Provides connection details.
• Provides data about TCP and UDP.

                  IPCONFIG COMMAND

• Displays all network settings.
• Identifies DHCP problems.
• Used with WIN-2k and later versions.
• Displays and resets DNS cache.
• Sets and displays DHCP class IDs for an adapter.

             WinIPCONFIG COMMAND

• Provides IP addressing details.
• Used for WIN-98 or earlier versions.
• Provides details such as IP address, subnet mask, default gateway, DHCP server, WINS server etc.

                        ARP COMMAND

• Links IP address of a node with its hardware address.
• Various ARP command option can be used to display or change the values in ARP table.

                      NbtSTAT COMMAND

• Resolves NetBIOS name resolution problems.
• Used when WINS server is not accessible.
• Displays protocol information and current TCP/IP connection using NetBIOS over TCP/IP (NBT).

                    ROUTE COMMAND

• Allows you to view and make changes in the IP routing table.
• Used to differentiate between routes to hosts and routers to networks by reading the network address of the destination.