Application and use of domain names related to the basic knowledge

First, terminology: A DNS MX record of the CNAME record records TTL
1, What is a Domain Name?
DNS is the domain of international or domestic, as well as Chinese domain names, and so do the domain name application to the IP address of the conversion process. IP address is the network logo on your site, the number of addresses, in order to remember simple, using domain names instead of ip address marking the site address. Analysis of the domain name by the DNS server to complete the work.

2, What is A record?
A (Address) record is used to designate the host name (or names) the corresponding IP address of record. Users of the site under the domain name server to point to their own web server on. At the same time, you can also set up secondary domain names.

3, What is the MX record?
E-mail routing records, users can e-mail under the domain name server to point to their own mail server, and then on its own can control all the mail settings. All you need to fill out the online server of your IP address, you can be under the domain name e-mail to all of your own to set the mail server.

4, What is a CNAME record?
: Alias record. This allows you to record a number of names mapped to the same computer. At the same time, WWW is commonly used to provide computer services and MAIL. For example, a computer known as the "host.mydomain.com" (A record). At the same time it provides MAIL and WWW service, user-friendly access to services. The computer can set up two alias (CNAME): WWW and MAIL. Both the full name of the alias on http://www.mydomain.com/ and "mail.mydomain.com". In fact they point to "host.mydomain.com".

5, What is the TTL value?
TTL value is the full name of the "survival time (Time To Live)", it's that simple DNS records in the DNS server cache of time. To understand the value of TTL, please see the following example:
Assuming that such a domain name myhost.abc.com (In fact, this is a DNS record, that is usually in the domain abc.com has named a host myhost) for the corresponding IP address of 1.1.1.1, the TTL for 10 minutes . The domain name or the records stored in a dns.abc.com known as the DNS server.


Second, there is now a user in a browser you type the address (or URL): http://myhost.abc.com/ at this time what will happen then?

The visitors designated by the DNS server (or his ISP, Internet service providers, to his dynamic distribution) 8.8.8.8 will attempt to explain his myhost.abc.com, of course, this 8.8.8.8 due to the DNS server does not contain myhost.abc.com this information could not be immediately resolved, but through the world of recursive DNS query, the ultimate target dns.abc.com this DNS server, dns.abc.com this DNS server will myhost.abc . com corresponding IP address 1.1.1.1 told 8.8.8.8 this DNS server, but then have to tell the user the results of 8.8.8.8. 8.8.8.8 In order to speed up the process after this record myhost.abc.com resolution, it will be just 1.1.1.1 of the results of a certain period of time, the TTL is the time during this period of time if the user has on myhost.abc.com The analysis of the records request, it tells the user directly to 1.1.1.1, when the TTL is also due to repeat the process above.


Third, why do I resolve not come into effect?
Each of the following reasons may lead to your analysis can not come into effect.
1, the DNS domain name did not request the right set of DNS. So that if you set the resolution, the DNS domain name must be ns1.dns-diy.com & ns2.dns-diy.com, or the other has to point to two The DNS 000 DNS.
2, domain names have not set the record of the resolution.

Fourth, how to check the DNS domain name has been set up as a valid DNS server?
You can manage domain names in the area of the platform on the right side of the page regions, to check whether the DNS settings are correct.
If you want to modify the DNS domain name registrars to the needs of the domain name management interface operation.

Five have already registered to modify the DNS, why DNS check or the old DNS?
Our DNS check is based on the DNS root servers based on current data, registered in the DNS may need to modify the 12-72 hours to be reflected in the root servers. DNS can come into effect, we have to check the DNS prevail.

Sixth, can resolve the entry into force, why they can not get the message?
Please check your MX records to set right;
Please check your post office server is set up correctly.
If you do not have their own mail server, you can use our e-mail forwarding.

Seven, set up MX records, why not valid?
SMTP most of the requirements of MX records point to a host name. Therefore, please MX records to a designated host name instead of IP addresses.
For example, let 218.5.1.249 as whatis.cn the mail server can be set up,

1, will mail.whatis.cn to resolve 218.5.1.249 ( "host" fill in "mail", "type" choose "A", "IP
Address / host name "fill in" 218.5.1.249 ", then" increase ")
2, whatis.cn set up the MX records for mail ( "host" column blank, "the type of" choice "MX", "IP address / host name" fill in "mail", then "increase")
3, in the 218.5.1.249 set, allowed to receive mail @ whatis.cn

If you are above the second step in the "host" column to fill in the "mail", said @ mail.whatis.cn sent to the e-mail received by the 218.5.1.249, which you may not be compatible with the meaning of this

Pat, why some host name with "." At the end, while others do not? What is different?
In order to "." At the end of the hostname that the full name of the host name (FQDN); rather than "." At the end of the host name that the domain name in the host name.
For example: 1, in Canada under the domain whatis.cn a CNAME record of the type of "abc" refers to the "123", abc.whatis.cn said 123.whatis.cn the resolution.
2, in the domain whatis.cn increase under a CNAME record of the type of "abc" refers to the "onlinenic.com.", So that abc.whatis.cn with the onlinenic.com resolution.

Nine, why "priority" is always set to "0"?
"Priority" only valid MX record, other types of records to ignore the priority.

10, Pan can be done to resolve it?
可以. In the "host" to fill the column "*."

11, DNS domain names and amend the resolution different?
And modify DNS DNS completely different meaning:

1, DNS refers to amend the DNS server (Domain Name System) changes.
If you own a separate DNS server, DNS to resolve this through the success of the domain name has been registered, you can choose to modify DNS operations (Note: To change the DNS domain name must be registered in the company or has been transferred to the success of my company's domain name) . Please visit the management of domain names - click on the corresponding domain-DNS Service to amend modify your DNS domain name information

2, DNS: IP address and domain name is the one mapping between, and their conversion as the work of the DNS, DNS is a need for the specialized DNS server (DNS) to complete.
If your host and domain name are successful, it would take to resolve to do if your DNS domain name is the first host of the default DNS, please visit the management of domain names - click on the appropriate domain name - Domain Name Service modify your domain name to resolve. If your name is not the first DNS server to resolve the host, and your DNS service provider where the contact to resolve issues.

Twelve Chinese and English domain name fees whether or not to amend DNS?
International English domain names, domain names can be amended in English domestic DNS, the service is free of charge.

13, URL forwarding path and do not hide hidden What is the difference between the path?
URL does not hide the path forward: for example: http://b.com/ point http://a.com/xxx/ (any directory); in the browser's address bar into the connected http://b.com/ The address bar will show the true address of the http://a.com/xxx/
Hide the URL path forward: for example: http://b.com/ point http://a.com/xxx/ (any directory); in the browser's address bar into the connected http://b.com/ Show the address bar or http://b.com/, but the point is http://a.com/xxx/.