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

in the daily Internet or office process, many people have encountered the situation that the network connection is normal, but they cannot open any webpages, which is likely to be caused by the failure of DNS. As the address translator in the network, DNS is responsible for converting the domain name into a recognizable Internet Protocol Address. Once it has a problem, the entire network access link will be interrupted. This article will deeply analyze the common causes of DNS failures, and provide a set of practical quick fixes to help you quickly locate and solve similar problems and restore normal network use.

What are the common manifestations of DNS failure?

to deal with the problem of DNS failure in a timely manner, we must first accurately identify its performance and avoid confusion with ordinary network problems.

1, page loading failure or error

this is the most typical performance of DNS failure, after entering the domain name in the browser, the page is loaded for a long time, and finally shows that the webpage cannot be accessed, the server cannot be found and other prompts, but the use of Internet Protocol Address to directly access some servers can be successful, which shows that there is a problem with the conversion of the domain name to IP.

2, abnormal network connection status

some devices will prompt DNS configuration errors in the network settings, or although it shows that it is connected to the network, it cannot perform any network operations, such as not being able to send messages, loading online videos, etc., which may also be a chain reaction caused by DNS failure.

3, some domain name access abnormality

there is also a case that some websites can be accessed normally, and the other part cannot be opened at all. This kind of selective access failure is most likely that the DNS server has a problem with the resolution of a specific domain name, which belongs to the local performance of DNS failure.

What are the common causes of DNS failure?

find the root cause of DNS failure, in order to repair more accurately, the common incentives are mainly concentrated in the server, network environment and local settings.

1, DNS server itself failure

Public DNS servers used by

users may stop serving due to excessive load, hardware failure or system maintenance, resulting in DNS failure. For example, operator DNS servers in some regions may experience resolution delays or failures due to excessive access during peak hours.

2, local network environment interference

router failure, loose network line or electromagnetic interference, etc., may affect the transmission of DNS resolution requests and cause DNS failure. For example, if the router runs for a long time and causes cache overflow, it will not be able to forward DNS resolution requests normally, resulting in the domain name cannot be converted to Internet Protocol Address.

3, the local DNS configuration error

input error when manually setting the DNS address, or the DNS address automatically obtained by the system is abnormal, it will directly lead to DNS failure. In addition, the network protection settings of some security software may also mistakenly intercept DNS resolution requests, resulting in the illusion of resolution failure.

How to quickly troubleshoot and locate DNS failures?

before the hands-on repair, through scientific troubleshooting steps to locate the specific links of DNS failure, blind operation can be avoided to waste time.

1, use the ping command to test basic connectivity

open the command prompt of the system, enter ping plus common public Internet Protocol Address, such as 8.8.8.8, if you can receive a response normally, indicating that the network basic connectivity is no problem, the probability is DNS failure; if the ping command does not respond, it may be a problem with the basic network connection.

2, use the nslookup command to test the parsing function

enter nslookup plus common domain names in the command prompt, such as www.baidu.com, if you return the prompt that the server cannot be found or the resolution timed out, you can determine that the DNS has failed; if you can return the corresponding Internet Protocol Address normally, it means that the DNS resolution function is normal, and the problem may be at the browser or other application level.

3, replacement equipment verification fault range

use other devices to connect to the same network, if other devices also have the same inability to access web pages, it means that DNS at the network level fails; if other devices can access the Internet normally, the failure is likely to occur on the local configuration of the current device.

What are the quick repair methods for DNS failures?

when the DNS failure is confirmed, you can select the corresponding repair method to quickly restore network access according to the troubleshooting results.

1, refresh the local DNS cache

the local device caches the resolved domain name and Internet Protocol Address, when the cache expires or an error occurs, it may cause a DNS failure. You can enter the ipconfig /flushdns command from the command prompt to clear the local DNS cache, and then try to access the web page. In most cases, the problem can be solved quickly.

2, change the public DNS server address

if the DNS failure caused by the operator DNS server, you can manually replace the DNS address with public DNS, such as Google's 8.8.8.8, 8.8.4.4, or domestic 114.114.114.114, the stability and resolution speed of these public DNS servers are relatively guaranteed, which can effectively avoid the failure caused by the operator DNS.

3, restart network devices and local devices

Temporary errors that

router or local device running for a long time can also cause DNS to fail. Turn off the router power and wait for 10 seconds to restart, and restart the local computer or mobile phone to let the network device and local system reset the network connection. Many glitches can be solved by this simple operation.

To sum up, DNS failure is a common network problem, its incentives cover the server, network environment and local configuration of multiple levels, by identifying typical performance, scientific investigation and positioning, and then with the refresh cache, change the DNS address and other methods, can quickly solve the problem. Daily use of the network, you can also regularly check the DNS configuration, choose a stable public DNS server, reduce the probability of DNS failure, to ensure the smooth network access.