In-depth analysis of the reasons for the DNS resolution failure and its solution

I do not know if you have encountered DNS resolution errors, sometimes we will encounter webpages that cannot be opened on the Internet, and sometimes the prompt is a DNS error. That is, there is a problem with the analysis. Let's analyze it together today.

First, what is the DNS resolution failure?

Generally speaking, the addresses like www.xtzj.com that we visit are called domain names, and it is well known that any host in the network is an IP address. To identify, that is, only know the IP address of this site to successfully achieve access operations.

However, because the IP address information is not well remembered, the name of the domain name appears on the network. When accessing, we need to enter the domain name of this good memory. The network will automatically have the corresponding domain name. A server that resolves to an IP address. This is the Dns server. The machine that can implement the DNS resolution function can be either its own computer or a computer in the network, but when DNS resolution is wrong, for example, parsing a domain name into a wrong IP address, or not knowing the corresponding domain name at all. When the IP address is, we can't access the corresponding site through the domain name. This is the DNS resolution failure.

The biggest symptom of DNS resolution failure is that there is no problem with accessing the IP address of the site. However, accessing his domain name will result in an error.

Second, how to solve DNS resolution failure:

When our computer has a DNS resolution failure, don't worry, the solution is very simple.

(1) Use nslookup to determine whether it is a DNS resolution fault:

To be 100% judged whether the DNS resolution fault needs to be solved by the system's own NSLOOKUP.

Step 1: Confirm that your system is Windows 2000 and Windows XP and above, then enter "CMD" by "Start -> Run -> Enter and enter command line mode.

Step 2: Enter the nslookup command and press Enter to enter the DNS resolution query interface.

The third step: The command line window will display the DNS server address used by the current system. For example, the author's Dns server IP is 202.106.0.20.

Step 4: Next enter the domain name of the site you are unable to access. For example, if the author enters www.softer.com, if it cannot be accessed, then the DNS resolution should not be normal. We will receive a prompt message for DNS request timed out, timeout was 2 seconds. This shows that our computer does have a DNS resolution failure.

Tip: If the DNS resolution is normal, it will feedback back to the correct IP address. For example, the author uses the address www.sohu.com for query analysis, and will get name:sohu.com, addresses: 61.135.133.103 , 61.135.133.104 information.

(2) Query whether the Dns server works normally:

At this time, we have to look at the DNS address used by our computer and query his operation.

Step 1: Confirm that your system is Windows 2000 and Windows XP and above, then enter "CMD" by "Start -> Run -> Enter and enter command line mode.

Step 2: Enter the ipconfig /all command to query the network parameters.

Step 3: In the ipconfig /all display information we can see a place to write DNS SERVERS, this is our DNS server address. For example, the author is 202.106.0.20 and 202.106.46.151. From this address, it can be seen that it is an external network address. If there is a parsing error in the external network DNS, we can replace the other Dns server address to solve the problem.

Step 4: If the internal network address of your company is displayed at the DNS server, then your company's DNS resolution is done to the company's internal DNS server. In this case, we need to check. This DNS server performs nslookup operations on the DNS server to see if it can be parsed normally. To solve the DNS service failure on the Dns server, the problem can generally be solved.