What should I do if the DNS server fails? Common causes and quick fixes

in the process of daily use of the network, many people have encountered the situation that the network signal is normal, but the webpage cannot be opened and the application content cannot be loaded. This is likely to be the fault of the DNS server. As the "address translator" in the network, DNS is responsible for converting the domain name into a recognizable Internet Protocol Address. Once a failure occurs, it will directly cut off the connection channel between the device and the network resources. This article will deeply analyze the common causes of DNS server failure, share practical methods for rapid troubleshooting and repair, and give effective prevention strategies to help you easily solve such network problems.

Common causes of DNS server failure?

want to quickly solve the DNS server failure, first of all to find the root cause of the problem, different incentives corresponding to the repair method is also very different.

1, abnormal network connection

this is a common external factor that causes DNS server failure, such as the loosening of the network cable between the router and the light cat, the fluctuation of the WiFi signal due to electromagnetic interference, or the temporary maintenance of the operator's network base station, will cause the device to fail to connect to the DNS server normally, and then the domain name resolution fails. In this case, the device usually prompts that the network cannot be connected, or the page shows "The server cannot be found" when loading.

2, DNS server itself failure

whether it is the default DNS server provided by the operator or the public DNS server set by the user, it may fail due to server maintenance, hardware damage, traffic overload and other issues. For example, if the operator's DNS server in a certain area is upgraded, the users in the area will collectively encounter DNS server failure and cannot resolve the domain name normally.

3, local device misconfiguration

if the user manually modifies the DNS server address, enters the wrong Internet Protocol Address, or does not configure the DNS parameters correctly after opening the proxy server, it will also cause DNS server failure. In addition, the network settings of the device are tampered with by malicious software, which will also cause the domain name resolution process to be abnormal and cannot access network resources normally.

Second, DNS server failure quick troubleshooting method?

when a DNS server failure is suspected, the problem can be quickly located through scientific troubleshooting steps to avoid wasting time with blind operations.

1 Test basic network connectivity

can first try to access the known Internet Protocol Address, such as entering the Internet Protocol Address of the public DNS server, if you can open the corresponding page normally, it means that there is no problem with the network connection itself, and the failure is likely to occur in the DNS resolution process; if you can't access it, It may be that the basic network connection is abnormal, and you need to check the network cable, WiFi signal and operator network status first.

2 Switch network environment test

If you use WiFi to encounter DNS server failure, you can switch to the mobile phone traffic network to try to access the same domain name, if the traffic network can be opened normally, indicating that the problem is in the current WiFi DNS settings or connections; if the traffic network can not access, it may be the DNS server itself fault, or there is a problem with the system settings of the device.

3 Use command line tools to detect

on the computer can enter the "nslookup" command through the cmd command line to query the Internet Protocol Address corresponding to the specified domain name, if the "server failed" or "can not find the domain name" prompt, you can confirm that the DNS server failure; if the normal return Internet Protocol Address, indicating that the DNS resolution is normal, the problem may be in the browser or application itself.

3. How to quickly repair the DNS server failure?

determine the root cause of the DNS server failure, you can take targeted repair measures to quickly restore the normal access function of the network.

1, troubleshoot and repair network connections

first check the network cable interface of the router and light cat to ensure that the network cable is plugged in tightly and not loose, restart the router and light cat, and wait for the device to re-establish the network connection; if it is a WiFi signal problem, you can try to get close to the router, or close the surrounding electrical appliances that may cause interference, such as microwave ovens, Bluetooth speakers, etc., to reduce the impact of electromagnetic interference on the signal.

2, switch, or reset DNS server addresses

if the default DNS server failure, you can manually switch to the public DNS server, such as commonly used domestic 114.114.114.114, 223.5.5.5, or foreign 8.8.8.8, find the DNS server option in the network settings of the device, enter the new Internet Protocol Address and save it; If you are not sure about the correct DNS address, you can also choose to automatically obtain the DNS server address, so that the device can re-obtain the available DNS information from the operator.

3, clear the local DNS cache

device will cache the resolved domain name and Internet Protocol Address for quick access next time, but if the cached information is wrong, it will also cause DNS server failure. At this time, you can enter the "ipconfig /flushdns" command in the command line of the computer to clear the local DNS cache; mobile phone users can clear the DNS cache information by restarting the device, or resetting the network in the network settings.

How to prevent the recurrence of DNS server failure?

solve the DNS server failure, taking some preventive measures can effectively reduce the probability of failure recurrence and improve the stability of network use.

1, set the alternate DNS server address

in the network settings of the device, in addition to setting the preferred DNS server address, you can also add an alternate DNS server address. When the preferred DNS server fails, the device will automatically switch to the standby server to ensure the normal progress of domain name resolution and avoid network outages.

2, regularly check the status of network equipment

develop the habit of regularly checking routers, light cats and other network devices, check whether the operating status indicator of the device is normal, clean up the dust on the surface of the device in time, and avoid failures due to hardware overheating; at the same time, regularly restart the network device to release the random access memory of the device, Reduce the risk of DNS server failure caused by long-term operation.

3, install security software

malicious software tampering with DNS settings is one of the common causes of DNS server failure, install regular security software, open real-time protection function, can effectively intercept the tampering behavior of malicious software, protect the network settings of the device security, avoid network access problems caused by DNS configuration tampering.

To sum up, DNS server failure is a common network problem, and its causes cover network connection, server itself, device configuration, etc. By investigating network connectivity, switching network environment, and using command line detection, the root cause of the fault can be quickly located, and then measures such as repairing network connections, switching DNS addresses, and clearing caches can be taken to quickly restore the network. Daily backup DNS settings, regular inspection of equipment, and installation of protection software can effectively reduce the probability of DNS server failure and ensure stable network operation.