The eight-way method cleverly resolves network connection faults

Building a network is relatively easy, but it is complicated to manage the network. Not to mention the various requirements that the user has put forward to you will keep you busy. It is troublesome to solve the network failure alone, because there are too many causes of network failure. However, as a network manager, it is not necessary to lose the courage to solve the problem. As long as we regulate the fault phenomenon, there are still rules to follow.

1. The connection indicator is not on

Observe that there are two indicators on the backend RJ45 side of the NIC. They are connection status indicators and signal transmission indicators respectively. In normal conditions, the connection status indicators are green and bright, and the signal indicators are red. Normally, they should not stop flashing. If we find the connection indicator light, that is, the green light is not on, it indicates that the connection between the nic and the hub or switch is faulty. To solve this problem, you can use the tester to perform segmentation troubleshooting. If multiple modules are interconnected from the switch to the NIC, you can use the binary method to quickly locate the problem. In general, this fault occurs mostly because the network cable is not firmly connected and the inferior crystal head is used. In addition, most of the fault points have problems at both ends of the connection. For example, the connection between the port of the switch and the network adapter connecting to the computer can be easily solved by using the tester.

2. Signal indicator light is not on

If the indicator light is not on, it indicates that there is no signal for transmission, but it is certain that the line is normal. If there is a signal transfer, use the replacement method to switch the network cable connected to the computer to another computer, or use a tester to check whether there is a signal transfer. If there is a signal transfer, it is a problem with the local Nic. In practice, it is proved that it is a common fault that the NIC causes no information transmission. In this case, you can first check whether the NIC is installed normally and whether the IP address is set incorrectly. You can Ping the IP address of the Local Machine. If you can Ping the general rules, the NIC is normal. If the problem persists, you can try to reinstall the NIC Driver. In addition, if you use an integrated Nic or a poor quality Nic, it is prone to instability, that is, all the settings are correct, however, the network is disconnected. You can disable the NIC and then enable it again, which also has unexpected results.

Iii. Speed Reduction

Many NICs use a 10 M/M Adaptive Nic. Although the default setting of the NIC is "Adaptive", some mismatched conditions may occur due to the speed of the switch or the method used to create the NIC. In this case, set the speed of the NIC to 10 MB. You can right-click "Local Connection" to open its Properties window. On the "General" tab, click "Configure" to switch the open Nic Properties window to the "advanced" tab, select "Link Speed/Duplex Mode" in the "properties" list, select "10 FullMode" from the "value" drop-down menu on the right, and click "OK" to save the settings.

4. Network Access failure caused by the firewall

In order to ensure security in the LAN, many friends have installed some firewalls. In this way, it is easy to cause some "false" faults, such as Ping failure, but access to the computer of the other party, and access to the Internet but QQ. It is easy to judge whether a fault is caused by a firewall. You only need to temporarily disable the firewall and then check whether the fault exists. The cause of such a fault is also very simple. For example, when a user uses IE to access a website for the first time, the firewall will ask whether the program is allowed to access the network, some users may use such settings when they are not allowed due to carelessness, which naturally leads to network disconnection. A thorough solution is to remove this restriction in the firewall. For example, if you are using Kingsoft network, you can open the window, switch to the "Application Rules" tab, find Internet Explorer items in it, and click "allow.

5. Strange network access failure

In the actual troubleshooting process, some large networks are prone to strange faults that fail over the entire network. It is strange to say that it is because all phenomena seem to be normal, indicators and configurations have been checked, and no problems exist, but the network is disconnected; what's even more, it is the occasional access from one or two computers in the process of being disconnected. In fact, this is a typical network storm, most of which occurs in some large and medium-sized networks. There are a lot of viruses in the network, and then the traffic between them is infected with each other. Because there are many computers in the network, the data transmission volume is large and the port is occupied directly, so that normal data cannot be transmitted. The most direct solution to this network storm caused by viruses is to find out the source of the storm. In this case, you only need to install a firewall on a computer on the network, such as Kingsoft network, after you enable the firewall, you will find that the firewall does not stop alerting. After you enable the firewall, you can see in the security log of the "security status" label that the firewall intercepts virus attacks from the same IP address, at this time, you only need to find out which computer is based on the IP address and disconnect it from the network for virus scanning and removal. Generally, the problem can be solved.

6. Network disconnection caused by configuration errors

The external manifestation of such a fault is that the network indicator is normal and can be pinged. Sometimes, intranet resources can be accessed, but Internet resources cannot be accessed, and sometimes the website can only be accessed through IP addresses, but cannot be accessed through the domain name. This is the result of a typical improper network configuration, that is, the correct Nic and DNS are not set. If the gateway settings are incorrect, the computer can only be accessed within the lan. If the DNS settings are incorrect, the system cannot resolve the access to the external website. In this case, you only need to open the Properties window of the local connection, open the "Internet Protocol (TCP/IP)" Properties window, and set the correct Default Gateway and DNS server address.

7. Access From Network peers fails

The network is smooth, and all the connections to Interne or LAN are normal, but they are not accessible when they access other computers on the LAN through network neighbors. There are many reasons for this failure. Here I can provide you with a simple solution. In the "run" window, access the shared folders on other computers in the network in the format of "computer name (IP address) Sharing name". This not only bypasses this fault, it is faster than accessing through a network neighbor.

8. Network disconnection caused by group policies

This type of fault mainly exists between Windows 2000, XP, and 2003 systems because the group policy is set to prohibit access from the network. Therefore, you can enter "Gpedit. msc and press Enter. In the displayed Group Policy window, select local computer policy-Computer Configuration-Windows Settings-Security Settings-local policy-User Privilege assignment ", double-click "Deny access to this computer from the network" on the right. In the displayed window, select and delete the account list.

Network connectivity is a complex and variable fault, but as long as we master its nature, understand the network construction steps, and be familiar with the fault-prone points, we can achieve constant failover, it is easy to solve network problems.