What should I do if DNS is abnormal? Full analysis of common causes and handling methods

in the process of daily use of the network, many people have encountered slow loading of web pages, unable to open designated websites or even completely disconnected from the network. After investigation, they often find that the root cause is DNS abnormalities. This problem seems to be a small trouble, but it will seriously affect office efficiency and Internet experience. This article will deeply disassemble the common causes of DNS abnormalities, systematically explain the corresponding troubleshooting and solutions, and share prevention skills to help you quickly locate and solve such network failures.

What are the typical manifestations of DNS abnormalities?

want to solve DNS abnormalities in a timely manner, we must first accurately identify its typical symptoms and avoid confusion with other network problems.

1, page loading failure or card

this is the most common performance of DNS abnormalities, enter the URL for a long time after the page display can not be accessed, or loading progress bar stagnant, refresh many times will not help, some pages may only load the text but no pictures.

2, certain websites cannot be accessed

if other websites can be opened normally, only one or a certain type of website cannot be accessed, the probability is that the domain name resolution error caused by DNS abnormality makes the browser unable to find the server address of the corresponding website.

3, the network connection shows normal but no network

the network icon of the computer or mobile phone shows that it is connected, but there is no response regardless of opening any web page. When using the network diagnostic tool to detect, it will prompt the domain name resolution failure, which is also a typical characteristic of DNS abnormalities.

Common causes of DNS abnormalities?

find the cause of DNS abnormality, is the key to solve the problem quickly, different reasons corresponding to the repair method is also different.

1, local DNS cache error

in order to speed up the domain name resolution, the device will automatically cache the resolved domain name information. When the cached information expires or there is an error, a DNS exception will be thrown, resulting in the inability to correctly resolve the new domain name.

2, network operator DNS failure

many users default to the DNS server provided by the operator, once the operator's DNS server maintenance, overload or failure, it will directly lead to DNS abnormalities in user equipment, unable to complete the normal domain name resolution.

3, router settings or failure

router as a network transit device, if its DNS settings are modified by mistake, or the router itself has firmware failure, hardware aging, it will also cause DNS abnormalities, making all devices connected to the router have network problems.

How to quickly troubleshoot and repair DNS abnormalities?

when it is confirmed that DNS is abnormal, it can be troubleshooted and repaired in the order from easy to difficult, and gradually solve the problem.

1, refresh the local DNS cache

this is the most basic operation to solve DNS exceptions, Windows users can enter the ipconfig /flushdns command through the command prompt, Mac users can enter the sudo killall -HUP mDNSResponder command at the end point, after the execution is completed, you can clear the wrong cache information and regain the correct resolution data.

2, manually replace the public DNS server

if the operator DNS server failure caused by DNS abnormalities, can be manually replaced by public DNS, such as domestic 114.114.114.114, foreign 8.8.8.8, these public DNS server stability and resolution speed are guaranteed, can effectively solve the domain name resolution problem.

3, restart or reset the router

try to restart the router first, wait 30 seconds before re-powering, many DNS abnormalities caused by temporary router failures can be solved in this way. If the restart is invalid, the router can be restored to factory settings, reconfigure network parameters, and eliminate the problem of wrong settings.

How to prevent DNS abnormalities from happening again?

solve DNS abnormalities, preventive measures can effectively reduce the probability of problems recurring and ensure long-term stability of the network.

1, clean DNS cache regularly

recommend manually cleaning the local DNS cache once a month to avoid DNS exceptions caused by the accumulation of error messages in the cache, or you can set up automatic cleaning with the help of third-party tools to reduce the trouble of manual operation.

2, use stable public DNS

compared with the operator's default DNS server, the public DNS is more stable, and the public DNS address with good reputation can be used for a long time to avoid DNS abnormalities caused by the operator's server failure.

3, regularly update the router firmware

router manufacturers will release firmware updates from time to time, fix known vulnerabilities and failures, and regularly update router firmware, which can effectively improve the stability of the router and reduce DNS abnormalities caused by router problems.

To sum up, DNS abnormalities are a common network failure, which is diverse and complex, but as long as you master the correct identification, troubleshooting and repair methods, you can quickly solve the problem. Daily cache cleaning, selection of stable DNS, updating router firmware and other preventive measures can also effectively reduce the probability of DNS abnormalities and make network use smoother.