Common Malfunction Of Switch And Its Solution（2）
Failure phenomenon: a computer room often appears a part of the computer can not access the server phenomenon. At first thought that the network wiring is not standard and the network card settings have been modified by the students, so the computer room administrators often test and reset the network configuration of the network line. But after repeated maintenance, the network connection of these computers At the end of the day, all the computers in this group were unable to access the Internet, and all the connection lights that were connected to the set of computers were flashing irregularly.
Cause of failure: the core switch is usually composed of main circuit board and power supply circuit board. The main factors that cause the circuit board not to work normally are: the components on the circuit board are damaged or the substrate is bad, the hardware note is not suitable and the hardware is updated, and the circuit board type caused by the compatibility problem is not suitable, and so on.
Solution: first of all, determine whether the main circuit board or power circuit board problems, first from the power supply part of the inspection, using a universal meter without the main circuit board load under the circumstances of the measurement, to see if the measured indicators are normal, If not normal. Instead of using an AT power supply, input the power supply to the main circuit board, and the indicator light on the front panel of the switch returns to normal brightness and color. However, the normal exchange of visits between the computers connected to the switch shows that there is a problem with the power supply circuit board. If the above operation is invalid, the problem should appear on the main circuit board. This is the most common fault in the switch, if the fiber plug or RJ-45 port is dirty, may cause port pollution and can not normal communication. What's more, many people usually like live plug and unplug connectors. In theory, it seems that it is not inappropriate, but in practice, this often inadvertently increases the incidence of port malfunctions; carelessness in handling. It can also cause physical damage to ports; the size of the purchased crystal head is too large to break the port when plugged into the switch. In addition, if a pair of twisted pair wires connected to the port are exposed outdoors, if the cable is struck by lightning, the connected switch port will be damaged.
Solution: in general, the port failure is an individual port damage, first check the problem of the computer, after eliminating the failure of the computer connected to the port, we can change the connected port to determine whether it is a port problem, If the problem can be solved after replacing the port, further determine what is the cause of the port. After the power is turned off, clean the port with an alcoholic cotton ball. If the port is damaged, the port will have to be replaced. In addition, whether the fiber port or twisted-pair RJ-45 port, you must be careful when plugging the connector, it is recommended that it is best not to plug live operation.