Fault diagnosis of intranet network in enterprise

In the day-to-day office of many enterprises, network operation and maintenance engineer is the normal work of the staff of the protection of God, if there is any problem the first time to find operation and maintenance. If the operation is not in the enterprise intranet problems, employees have no way, let the time lost in vain, the work is delayed, now not afraid, small series for you to organize some of the LAN network accident diagnosis cases, let you also cameo under the addiction of Engineers.

1. Failure phenomenon: Internet cafes all computers on the entire LAN can not be on the Internet.

Analysis, exclude: Server system work is normal, whether the server dropped the line, the modem is working properly, the local work is normal.

2. Symptom: The "error 678" or "error 650" prompt box appears on the computer screen.

Analysis, exclusion: Usually you dial the server line busier, busy, temporarily unable to connect, you can go in a while and continue to redial.

3. Symptom: The computer screen appears "error 680: No dial tone." Please check that the modem is properly connected to the phone line. "or" There is no dialtone. Make sure your Modem are connected to the phone line properly. " The Prompt box.

Analysis, exclude: Detect whether the modem work is normal, whether to open, check the phone line is normal, whether the correct access to the modem, the connector has no loose.

4. Symptom: computer screen appears "The Modem is being used by another dial-up networding connection or another program." Disconnect the connection or close the Program,and then try again "prompt box.

Analyze, exclude: Check if another program is using the modem, and check the modem for conflicts with the port.

5. Symptom: Network adapter (NIC) settings conflict with computer resources.

Analysis, exclusion: Avoid conflicts with other resources of the computer by adjusting the IRQ and I/O values in the network card resource. In some cases, it is also necessary to adjust the conflict with other resources by setting the motherboard jumpers.

6. Failure phenomenon: Internet café lan other clients in the "Network Neighborhood" can see each other, and only a computer who can not see it, it also can not see other computers. (Prerequisite: The LAN of the Internet café is connected to the Star-type network structure through the hub or switch)

Analysis, exclusion: Check whether this computer system is working properly; Check the network configuration of this computer, check that the NIC on this computer is working properly, check the network card settings on this computer for conflicts with other resources, check the network cable for disconnection, and check that the network cable connector contact is normal.

7. Failure phenomenon: Internet café LAN has two network segments, of which a network segment of all computers can not be on the Internet. (Prerequisite: The Internet café lan through two hub or switch to connect two network segments)

Analysis, exclusion: Two network segments of the main line is broken or the joints at both ends of the joint at the junction of bad. Check the settings for the network segment in the server.

8. Failure phenomenon: Internet café lan All computers in the "Network Neighborhood" can not see each other. (Prerequisite: The LAN of the Internet café is connected to the Star-type network structure through the hub or switch)

Analyze, exclude: Check whether the hub or switch is working properly.

9. Failure phenomenon: Internet café lan in a client computer in the "Network Neighborhood" can see the server, but is not on the Internet. (Prerequisite: The server refers to the proxy Internet cafes LAN other aircraft on the Internet computer, to the same below)

Analysis, exclusion: Check the settings of this client TCP/IP protocol, check the settings of IE in this client computer, and check the server for settings on this client computer.

10. Symptom: The computer screen appears "The computer you are dialing to not answering." Try again later the prompt box.

Analysis, exclusion: Telephone system failure or line busy, later redial.

11. Symptom: The computer screen appears "Connection to xx.xx.xx." was terminated. Do you want to reconnect? "The Prompt box.

Analysis, exclusion: Phone line interruption causes the connection between the Dial-up connection software and the ISP host to be interrupted, and then try again.

12. Symptom: The computer screen appears "The computer is isn't receiving a response from the" Modem. Check that this modem is plugged In,and if necessary,turn to the modem off, and then the prompt box for turn it back on.

Analyze, exclude: Check that the modem is powered on and check that the cable connected to the modem is properly connected.

13. Failure phenomenon: The computer screen appears "Modem is not responding" prompt box.

Analysis, exclusion: Indicates that the modem is not responding, checks the modem for power on, checks that the cable connected to the modem is connected properly, and the modem is corrupted.

14. The symptom: The computer screen appears "NO CARRIER" the prompt information.

Analysis, exclusion: indicates no carrier signal. This is not a normal shutdown of the modem application or phone line failure, check that the cable connected to the modem is properly connected, and check that the modem is powered on.

15. Symptom: The "No dialtone" prompt box appears on the computer screen.

Analyze, exclude: indicates no dial sound; Check that the phone line is properly connected to the modem.

16. Symptom: When the "Disconnected" appears on the computer screen.

Analysis, exclusion: Indicates termination of the connection, if the prompt appears when dialing, check the power of the modem is turned on, if the hint is used in the process, check whether the phone is used by people.

17. Failure phenomenon: Internet café lan In addition to the server can be Internet access to other clients are not available.

Analyze, exclude: Check whether the hub or switch is working properly; check that the network portion of the server connected to the hub or switch (including: network adapters, network cables, connectors, networking configuration) is working properly; check that the software on the server that is acting on the internet starts and runs normally;

18. Failure phenomenon: dial-up Internet operation, moden no dial sound, always connected to the Internet, Moden on the light also does not flash.

Analysis, exclude: The phone line is busy, connect the moden of the server (including: wiring, connectors) is normal, whether the telephone line is normal, there is no noise interference, the dial-up network configuration is correct; Moden If the configuration settings are correct, check that the audio or pulse mode of the dial tone is normal.

19. Failure phenomenon: The system does not detect Moden (if Moden is normal).

Analysis, exclusion: Reinstall the Moden, pay attention to the correct location of the communication port.

20. Symptom: Internet connection speed is too slow.

Analysis, exclusion: Check whether the proxy server system set the port connection speed in Dial-Up Networking is the maximum set, the line is normal, the speed of the connection can be improved by optimizing the Moden settings, and the speed of the Internet can be improved by modifying the registry, and whether there are many clients on the Internet; It is normal that the connection speed is too slow.