Solve the problem of DNS server unavailability

Title: Methods to solve the problem of DNS server unavailability

Introduction:
DNS (Domain Name System) is a system used to convert domain names into IP addresses. When the DNS server is unavailable, we will not be able to access the Internet normally because the domain name cannot be resolved to the corresponding IP address. This article will introduce how to solve the problem of DNS server unavailability and help readers find appropriate solutions.

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Step one: Confirm the source of the problem
When we cannot access the Internet, we first need to confirm whether it is a DNS server problem. This can be verified by trying to visit other websites or using a different device (such as a mobile phone). If other devices are also unable to access the Internet, then it is most likely because the DNS server is unavailable.

Step 2: Check the network connection
After confirming that it is a DNS server problem, we need to check the local network connection. You can try the following methods:

1. Make sure the power cord of the network device (such as router, modem) is plugged in and the device is working properly.
2. Check whether the network cable is loose or damaged, and try to replug and unplug the cable.
3. Restart the network device by turning off the power of the device, waiting for a few minutes and then restarting it.

Step 3: Change DNS server settings
If the network connection is normal but the DNS server is still unavailable, we can try to change the DNS server settings. Here are two common methods:

1. Use a public DNS server: Change the DNS server settings of your local computer or router to a public DNS server, such as Google's 8.8.8.8 or Cloudflare's 1.1.1.1. For specific operation methods, please refer to the user manual or official website of the operating system or router.
2. Refresh DNS cache: DNS cache sometimes causes connection problems. You can clear the DNS cache with the following command. In the Windows operating system, open the command prompt window (CMD), enter the command: ipconfig /flushdns, and then press the Enter key to execute. In Mac operating system, enter the command in the terminal: sudo killall -HUP mDNSResponder.

Step 4: Contact ISP or network administrator
If the above methods still cannot solve the problem of DNS server unavailability, we recommend contacting your Internet Service Provider (ISP) or network administrator members to report the problem and seek further assistance.

Conclusion:
When the DNS server is unavailable, we can solve the problem by confirming the source of the problem, checking the network connection, changing the DNS server settings, and contacting the ISP or network administrator. Choosing the appropriate method depends on the specific situation and type of equipment. I hope this article can provide some help to readers in solving the problem of DNS server unavailability.

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