What should I do if the DNS service fails? Cause analysis and quick fix methods

when you open the browser but can't load the webpage, or pop up the prompt that can't resolve the domain name, you are likely to encounter DNS service-related problems. As a bridge between domain names and Internet Protocol Addresses, once a failure occurs, it will directly affect the network access experience. This article will deeply dismantle the various incentives for DNS service failure, and provide a quick repair solution that can be implemented. From the basic row to professional debugging, it will help you restore the normal access function of the network step by step. It can be easily operated without complicated technical background.

What are the common causes of DNS service failure?

to solve the problem of DNS service failure, we must first clarify the root cause of the failure, and the repair direction corresponding to different incentives is quite different.

1, local network equipment failure

routers, light cats and other network devices run for a long time, there may be problems such as cache overflow and program cards, which directly lead to the failure of DNS resolution requests to be transmitted normally, resulting in DNS service failure. In addition, the aging of equipment hardware and the loosening of interfaces will also affect the stability of DNS signals, resulting in intermittent service failures.

2, the local DNS configuration error

some users manually modify the network configuration, they may enter the wrong DNS server address by mistake, or open unnecessary proxy services to interfere with the DNS resolution process. In some cases, the DNS address automatically obtained by the system fails and cannot complete the conversion of domain name to IP, which is ultimately manifested as DNS service failure.

3, operator DNS service abnormal

when the operator's DNS server encounters traffic overload, hardware failure or maintenance upgrade, there will be a large area of DNS service failure problems, such failures cover a wide range, multiple users in the same area will be affected, not a single device problem.

What are the basic troubleshooting methods for DNS service failure?

quickly locate the general direction of DNS service failure through basic troubleshooting before making complex repairs, saving fault processing time.

1, test network connectivity

open the command prompt, enter the ping command to test the public Internet Protocol Address, such as 8.8.8.8, if it can be connected normally, it means that there is no problem with the network hardware and the operator line, and the failure is likely to occur in the DNS resolution process; if it cannot be connected, it is necessary to troubleshoot the network connection itself.

2 Switch network environment test

try to connect to other available networks, such as mobile phone hotspots, if you can access the Internet normally after switching, it means that the original network environment has incentives for DNS service failure; if the domain name cannot be resolved normally after switching, it may be a problem at the local configuration or system level of the device.

What are the quick fixes for DNS service failure?

for the failure of DNS service caused by different incentives, we can take the following repair solutions to gradually restore the DNS resolution function.

1, restart network devices and end point

this is one of the most basic and effective ways to solve DNS service failure. Turn off the power of the router and light cat first, wait 10 to 15 seconds before restarting, and restart the end point device such as the computer or mobile phone. The restart operation can empty the cache of the network device and reset the DNS resolution process. Most temporary failures can be solved by this method.

2, manually replace the public DNS server

If the DNS service fails due to local DNS configuration or operator DNS failure, you can manually replace it with a public DNS server. Commonly used public DNS include Google's 8.8.8.8, 8.8.4.4, domestic 114.114.114.114, etc. These servers have high stability and fast resolution speed, which can effectively avoid network access problems caused by DNS server failure.

3, refresh the local DNS cache

Windows system can enter the ipconfig /flushdns command at the command prompt, Mac system can empty the locally stored DNS cache with the sudo killall -HUP mDNSResponder command. When there is an expired or wrong resolution record in the cache, the DNS service will fail, and the correct resolution information can be retrieved after refreshing the cache.

How to prevent DNS service failure from happening again?

solve the current DNS service failure problem, you can also reduce the probability of failure again through some measures to improve the stability of network use.

1, regular maintenance of network equipment

restart the router and light cat regularly once a week to avoid cache garbage generated by the long-term operation of the device; at the same time, check the firmware version of the device, install the update patch pushed by the official in time, fix the possible DNS resolution vulnerabilities, and prevent DNS service failure from the hardware level.

2, set up dual DNS server address

set the primary DNS and standby DNS server addresses simultaneously in the network configuration, when the primary DNS server fails, the system will automatically switch to the standby server to avoid DNS service failure caused by a single DNS failure, and further improve the reliability of DNS resolution.

To sum up, DNS service failure is a common network failure, and the inducements cover equipment failure, misconfiguration, abnormal service of operators and other aspects. When solving the problem, the root cause can be located through basic investigation, and then restarted the device, replaced the public DNS, refreshed the cache and other methods. Finally, the failure recurrence can be prevented by regular maintenance of equipment and setting up double DNS. As long as you follow the steps, you can quickly restore the normal access function of the network and reduce the trouble caused by DNS service failure.