Basic Domain Name application knowledge

Basic Domain Name application knowledge
I. Glossary: domain name resolution a record MX record cname record TTL
1. What is domain name resolution?
Domain name resolution is the process of converting the domain name to the IP address after applying for an international domain name or a domestic domain name or a Chinese domain name. An IP address is a digital address that identifies your site on the Internet. To make it easy to remember, use a domain name instead of an IP address to identify the site address. Domain name resolution is completed by the DNS server.

2. What is a record?
The A (Address) record is used to specify the IP address record corresponding to the Host Name (or domain name. You can direct the website server under this domain name to your web server. You can also set a second-level domain name for your domain name.

3. What is an MX record?
The mail route record. You can direct the mail server under the domain name to your own mail server, and then you can control all mailbox settings on your own. You only need to enter the IP address of your server online to transfer all emails under your domain name to your own email server.

4. What is a cname record?
That is, the alias record. This record allows you to map multiple names to the same computer. It is usually used on computers that provide both WWW and mail services. For example, there is a computer named "host.mydomain.com" (a record ). It provides WWW and mail services at the same time, in order to facilitate user access to the service. You can set two aliases (cname) for the computer: WWW and mail. The full names of these two aliases are http://www.mydomain.com/and “mail.mydomain.com ". In fact, they all point to "host.mydomain.com ".

5. What is the TTL value?
The full name of TTL value is "time to live". Simply put, it indicates the cache time of DNS records on the DNS server. To understand the TTL value, take a look at the following example:
Assume that the IP address of the domain name myhost.abc.com (in fact, this is a DNS record, which usually indicates that there is a host named myhost in the abc.com domain) is 1.1.1.1, and its TTL is 10 minutes. This domain name or record is stored on a DNS server named dns.abc.com.

2. Now there is a user in the browser to enter the address (also known as URL): http://myhost.abc.com/what will happen at this time?

The DNS server specified by the visitor (or its ISP, Internet service provider, which is dynamically allocated to him) 8.8.8.8 tries to explain myhost.abc.com to him, of course, because the DNS server 8.8.8.8 does not contain the message "myhost.abc.com", it cannot be resolved immediately. However, after recursive queries by global DNS, the DNS server "dns.abc.com" is finally located, dns.abc.com the DNS server returns the IP address of myhost.abc.com

1.1.1.1 tells 8.8.8.8 about this DNS server, but 8.8.8.8.8 tells the user the result. 8.8.8.8 in order to accelerate the resolution of the myhost.abc.com record in the future, the 1.1.1.1 result will be retained for a period of time. This is the TTL time, during this period, if the user has another resolution request for the myhost.abc.com record, it will directly tell the user 1.1.1.1, when

The above process will be repeated when the TTL expires.

3. Why does my resolution not take effect?
Each of the following causes may cause your resolution to fail.
1. the DNS of the domain name is not set to the correct DNS as required. for your resolution settings, the domain name's DNS must be a ns1.dns-diy.com & ns2.dns-diy.com, or another DNS that has been directed to the two DNS.
2. No resolution records have been set for the domain name.

4. How can I check whether the DNS of a domain name has been set as a valid DNS server?
You can check whether the DNS settings are correct in the right area of the operating platform page of the domain name management area.
If you want to modify the DNS of a domain name, you need to go to the domain name management interface of the Registrar.

5. I have modified the DNS at the Registrar. Why does the DNS check the old DNS?
Our DNS check is based on the current data of the DNS root server. It may take 12-72 hours to modify the DNS at the Registrar to be reflected on the root server. If domain name resolution takes effect, our DNS check prevails.

6. Why can't I receive emails?

Check whether your MX record is set correctly;
Check whether your post office server is set correctly.
If you do not have your own email server, you can use our email forwarding service.

7. Why is the MX record invalid?
Most SMTP requests an MX record to point to a host name. Therefore, specify an MX record to a host name instead of an IP address.
For example, you can set 218.5.1.249 as the email server of whatis.cn,

1. Resolve mail.whatis.cn to 218.5.1.249 (enter "mail" in the "host name" column, select "A" for "type", and enter "218.5.1.249" in the "IP Address/Host Name" column.

And then press "add ")
2. Set the MX record of whatis.cn to mail (leave it blank in the "host name" column, select "MX" for "type", and enter "mail" in the "IP Address/Host Name" column ", then press "add ")
3. Configure 218.5.1.249 to receive emails from @ whatis.cn.

If you fill in "mail" in the "host name" column in step 2, it indicates that the email sent to @ mail.whatis.cn is received by 218.5.1.249, which may not meet your meaning.

8. Why do some host names end with "." while others do not? What's the difference?
The host name ending with "." indicates the full name (FQDN) of the Host Name, rather than the host name ending.
Example: 1. Adding a cname record "ABC" under the whatis.cn domain indicates "123", then abc.whatis.cn indicates the resolution of 123.whatis.cn.
2. Adding a cname record "ABC" under whatis.cn indicates "onlinenic.com.". Then abc.whatis.cn indicates that onlinenic.com is used for parsing.

9. Why is the "Priority" always set to "0 "?
"Priority" is only valid for MX records. Priority is ignored for other types of records.

10. Can I perform Pan resolution?
Yes. Enter "*" in the "host name" field.

11. What is the difference between DNS modification and domain name resolution?
DNS modification and domain name resolution have different meanings:
　　
1. DNS Modification refers to the modification of the domain name system.
If you have an independent DNS server and want to use this DNS to resolve a domain name that has been successfully registered, you can select DNS to modify the business (note: the domain name to be changed must be registered in our company or successfully transferred to our company ). Please log on to the domain name management area and click the appropriate domain name-DNS modification area to modify your domain name DNS information
　　
2. domain name resolution: domain names and IP addresses correspond one by one. The conversion between them is called domain name resolution. domain name resolution must be completed by a dedicated domain name resolution server (DNS.
If both your host and domain name are successful, resolution is required. If your domain name DNS is the default DNS of the first host, please log on to the domain name management area and click the corresponding domain name-domain name resolution area to modify your domain name resolution. If your DNS is not the resolution server of the first host, contact your DNS service provider.
　　
12. Do I charge for modifying the DNS for an English domain name?
You can modify the DNS for International and Domestic English domain names. This service is free of charge.

13. What is the difference between a URL forwarding hidden path and a non-hidden path?
Do not hide path URL forwarding: for example, http:// B .com/ http://a.com/xxx/ (any directory); enter http:// B .com/in the address bar of the browser to display the correct address http://a.com/xxx/
URL forwarding of hidden paths: for example, http:// B .com/refers to http://a.com/xxx/ (any directory). In the address bar of the browser, enter "dig.

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