What should I do if DNS resolution is abnormal? Detailed explanation of common causes and handling methods

in the process of daily use of the network, many people have encountered the situation that the network connection is normal, but the specific website cannot be opened, and even all websites fail to load. This is most likely a problem caused by abnormal DNS resolution. As the "address translator" in the network, DNS is responsible for converting the domain name into the Internet Protocol Address that the server can recognize. Once there is an abnormality, it will directly block the connection between the user and the website. This article will deeply analyze the common causes of DNS resolution abnormalities and provide a complete set of troubleshooting and solutions to help you quickly restore network access.

What conditions can cause DNS resolution exceptions?

to solve the abnormal problem of DNS resolution, it is first necessary to clarify its triggering reasons. Different incentives correspond to different repair directions, and precise positioning can solve the problem efficiently.

1, the local DNS configuration error

this is one of the common reasons for DNS resolution abnormalities. For example, if the user manually modifies the DNS address and enters the wrong IP, or the DNS address automatically obtained by the system is deviated, the domain name cannot be translated normally. Some users may also cause problems due to address input errors after switching third-party DNS in order to improve access speed.

2, DNS server failure

whether it is the default DNS server provided by the operator, or a third-party public DNS server, there may be downtime due to hardware failure, system maintenance or overload of visits.

3, network environment interference

router failure, network line aging or ARP attacks in the local area network, it may interfere with the transmission of DNS resolution requests, resulting in the request not being delivered to the server, or the server's response cannot be returned to the user, and eventually cause DNS resolution abnormalities.

How to initially troubleshoot DNS resolution abnormalities?

encounter DNS resolution exception, do not rush to make complex settings modification, first through simple troubleshooting steps to narrow the scope of the problem, can save a lot of time and effort.

1 Test basic network connectivity

first try to access multiple different types of websites, if only individual websites can not be opened, it may be the problem of the website itself; if all websites can not be accessed, and then test the public Internet Protocol Address through the ping command, such as ping 8.8.8.8, if it can be connected normally, indicating that the network itself is not faulty, the problem is likely to be abnormal DNS resolution.

2, replacement equipment verification problem

use other devices under the same network to try to access the website, if other devices can access normally, indicating that the problem lies in the DNS configuration of the current device; if all devices cannot be accessed, then it may be a DNS resolution exception caused by the router or an external DNS server.

What are the basic repair methods for DNS resolution abnormalities?

for common DNS resolution abnormal problems, we can start from the basic repair methods, these operations are simple and easy to use, and in most cases can solve the problem quickly.

1, refresh the local DNS cache

system will automatically cache the resolved domain name and IP correspondence. When the cache data expires or there is an error, a DNS resolution exception will be thrown. At this time, you can perform the operation of refreshing the cache through the command line. Windows systems can enter ipconfig /flushdns in the command prompt, Mac systems can enter sudo killall -HUP mDNSResponder in the end point, and then try to visit the website after completion.

2, reset the local DNS configuration

if the manually configured DNS address is wrong, it can be reset to the automatic acquisition mode, allowing the network to automatically assign the available DNS server address; it can also be manually replaced with a public DNS address, such as Google's 8.8.8.8, 8.8.4.4, or domestic 114.114.114.114, these public DNS stability is strong, can effectively reduce the probability of DNS resolution abnormalities.

How to deal with DNS resolution exceptions in complex scenarios?

if the basic method can not solve the DNS resolution abnormality, you need to consider the problem in complex scenarios, such as network equipment failure or external network interference, at this time need to conduct a more in-depth investigation.

1, check and restart network devices

long-term operation of the router may cause cache overflow or program card, which may cause DNS resolution abnormalities. You can turn off the router power first, wait 10 to 15 seconds before reconnecting the power, and then test the network access after the router restarts. If the problem persists after restart, you can try to restore the router's factory settings and reconfigure the network parameters.

2, contact the operator to troubleshoot the line problem

If all devices under the same network have abnormal DNS resolution and cannot be solved after replacing the public DNS, it may be that the operator's network line fails or the DNS server area fails. At this time, you can contact the operator's customer service staff to give feedback on the specific situation and let the technicians conduct professional investigation and repair.

To sum up, DNS resolution abnormalities are a common network problem, and their causes cover local configuration, server status, network environment, etc. When encountering this problem, you can narrow the scope through basic troubleshooting, and then try to refresh the cache, reset the configuration, and restart the device in turn. If it still cannot be restored, you can contact the operator for professional support. As long as you follow the steps to troubleshoot step by step, you can quickly locate and solve DNS resolution abnormalities and restore normal network access experience.