【 Weak current College 】 go; addressing the network card hardware damage formation of LAN doesn't work (2)

Trouble searching

Although LAN cannot be connected scenes have been successfully cleared but the branches to a colleague-usual analogy, examination of net-man said why broadcast storm scene only affect their offices LAN network without affecting the entire unit of LAN network? since the offices of the LAN is that units Centre exchange machine direct access to the external network, connecting to the computer center exchange machine all LAN should be can't access the external network is on!

With regard to such doubts, the net-think of the offices of exchange machine was originally D-Link a second floor is equipped with all the Exchange machine directly connected to the mission station in practice are in the same broadcast domain, all once the network broadcast storm scene, so that all the tasks in the LAN will be clearly affect the station.

However, with regard to the entire organization, in order to be effective for a local area network to improve the efficiency of the unit's LAN, prevent some tasks is not a legitimate user to execute malicious attack units LAN, we advance in the Centre of the Exchange machine Division in many different branches to VLAN, local area would have been a VLAN, broadcast storm is not broadcast in the VLAN implementation between the units of other LAN is not affected.

Clearly, in a larger local area network environment, we can divide the appropriate VLAN resolution, to guarantee the security of network communications and enhance network communication fixed.

Order summary

If the network cannot be connected illnesses, we can first try to resolve other network using a network connectivity test, for example, to search for other tasks in the network, or that the Web testing in local area network access functions to find purpose mission station and so on. If another type of network application using normal, such as local tasks station although it is not possible to access Internet network, but they can be perceived in the my network places, or to other tasks you can use the ping command to test the other task station IP address connectivity, so you can confirm that the network connectivity aspects can really exists wrong. If we cannot properly when used with other network, you should continue to perform the following test.

The first surveys of local tasks station NIC lights task form can not be normal. General terms, the task stood not access network, the network card is equipped with lights flashing slowly, while in the access network and transport information, card lights blink faster. If the network card is equipped with the lamp does not light, perhaps long-lasting, it means that there is something wrong with the local mission station. If the network card is equipped with lights form is not working properly, so we'd better cut off the power to perform network tasks station replacement operation. If the network card lights flash forms correctly, we can continue the following examination.

Secondly that the ping command to perform the test action. First on 127.0.0.1 address or local tasks station IP address, see the network adapter is equipped with, as well as network protocol can task properly. If the above address to Ping Tung, which means that local tasks station network card is equipped with, as well as the communication protocol of the configuration is correct, the question was to attack on the local LAN network tasks and physical interface. Therefore, at this point we should test the network connectivity cable and AC machine task form. If the address cannot Ping Tung, that indicate the local task station network card equipped or TCP/IP communications protocols have questions.

Here we should perform testing on adapter is equipped with. In turn, click "start"/"configuration"/"Control Panel" command from the Control Panel window, open system equipped with a maintenance window to see where you can find the network adapter, or the network adapter in the chart above can be red or yellow flags, if any, that have not been marked cards equipped with the correct device, we need to do not have good network adapter is equipped with a direct deleted after you refresh it, local tasks station system, then follow the right way to resupply a card equipped with sequencing of driving and at the same time need to be configured for the network card is equipped with the appropriate network protocols, use the test at the beginning again. If the network card is equipped with a device that cannot be correctly, that indicate the network card is equipped with a hardware damage to attack, this time we only can adopt is to replace a piece of new cards a try.

In combating card equipped with elements, we are here to be on the network protocol elements perform troubleshooting. We can stand in the local task, in turn, the system desktop, click the "start"/"run" command in the pop-up system text box, enter "cmd" command, click the Enter key, the system interface to switch to the MS-DOS window, in the window of the command line to perform string command "ipconfig/all" and will be able to see clearly intuitive local tasks do not have the correct device stand good TCP/IP Protocol, and also be able to see the local mission station IP address, subnet mask, acquiescence gateway, DNS domain name, analysis services, and other parameters can be configured correctly. If there is no device-aware communication protocol, or does not perform properly configure the communication protocol, we must reboot device and configure your protocol, and then restart the local mission station. If the local task station has good communications protocols, device we hurt to carefully examine the various network protocols can not correctly configured. If communication protocol configuration in case of doubt, we can perform on the relevant parameters directly, that is complete restart the local task station system, at the beginning and then do one of the network by using the test.

Assuming the above elements have been swept away, then we can distinguish local tasks station initially does not exist. At this point, we can converge to similar to the exchange of other tasks relating to the implementation on the network using a test. If other tasks station has the network cannot be connected spectacle, confirm that the NIC is equipped with, as well as communication protocol configuration are correct, you can exchange basic identification is machine equipped with attack area. In order to perform the confirmation, we can try to replace the additionA mission station continue to perform tests to determine the Exchange machine equipped with could really exist. If other tasks stand test results everything works, then we will be able to identify defective attack in task and LAN network physical interface.