How do I make MX resolution records for domain names? --------------------------------------------------------------------------------
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, to set 218.5.1.249 as the email server of whatis.cn, resolve mail.whatis.cn to 218.5.1.249 (fill in "mail" in the "host name" column, and select "A" as the "type ", fill in "218.5.1.249" in "IP Address/Host Name", and then press "add ")
Set the MX record of whatis.cn to mail (the "host name" column is left blank, select "MX" for "type", and enter "mail" for "IP Address/Host Name ", then press "add ")
Set 218.5.1.249 to allow @ whatis.cn emails to be received.
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 comply with your meaning. What is a domain name? What makes a domain name?
A domain name is the name used to search for a website on the internet. It is an important identifier on the internet and is equivalent to a host's house number. Each host corresponds to an IP address. Each IP address consists of a series of numbers, such as 101.25.11.34. In order to facilitate memory, people use domain names instead of these numbers to search for hosts, such as mydomain.com. Each domain name corresponds to an IP address. people enter the domain name, and then the Domain Name Server (DNS) resolves it into an IP address to find the corresponding website. Domain names are required for each website or EMAIL. An English international domain name can contain up to 67 characters (including suffixes) and can contain English letters, Arabic numerals, and hyphens, each level can contain up to 22 letters. The length of a third-level domain name in China cannot exceed 20 characters. What is DNS?
Domain Name System (DNS) is the Domain Name resolution server. its role on the Internet is to convert a domain name into an IP address that can be recognized by the network. for example, the input http://www.163.com/will be automatically converted to 202.108.42.72. 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. What is an NS record?
The NS (Name Server) record is a Domain Name Server record, used to specify the DNS Server to which the domain Name is resolved. What is an alias record (CNAME )?
It is also called a canonical name. 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 www.mydomain.com and mail.mydomain.com ". In fact, they all point to "host.mydomain.com ". What is wildcard domain name resolution?
Wildcard domain name resolution is defined as: the customer's domain name a.com, under which * .a.com all resolved to the same IP address. For example, if B .a.com is set, it will automatically resolve it to the same IP address as a.com. What is an MX record?
The MX (Mail Exchanger) record is a Mail exchange Record pointing to an email server. It is used to locate the email server based on the recipient's address suffix when the email system sends an email. For example, when a user on the Internet wants to send a letter to a user@mydomain.com, the user's email system looks for the MX record for the domain name mydomain.com through DNS, if the MX record exists, the user's computer sends the email to the email server specified by the MX record. Methods for checking the existence of MX records
A very useful tool for DNS query is nslookup, which can be used to query various data in DNS. You can directly run nslookup in Windows command line to enter an interactive mode, where you can query various types of DNS data.
DNS name resolution data can be of different types, including the SOA type data with the parameter set for this zone, and the type data with the IP address corresponding to the parameter set for this zone, there is MX data set for mail exchange. These different types of data can be queried through the nslookup interactive mode. During the Query Process, you can use the set type command to set the corresponding Query type.
For example:
C: \> nslookup
Default Server: [202.106.184.166]
Address: 202.106.184.166> set type = mx
> Sina.com.cn
Default Server: [202.106.184.166]
Address: 202.106.184.166Non-authoritative answer:
Sina.com.cn MX preference = 10, mail exchanger = sinamx.sina.com.cnsina.com.cn nameserver = ns1.sina.com.cn
Sina.com.cn nameserver = ns3.sina.com.cn
Sinamx.sina.com.cn internet address = 202.106.187.179
Sinamx.sina.com.cn internet address = 202.106.182.230
Ns1.sina.com.cn internet address = 202.106.184.166
Ns3.sina.com.cn internet address = 202.108.44.55 if the MX record of a domain name does not exist, a message similar to the following appears:
C: \> nslookup
> Set type = mx
> Amaxit.com.cn
Default Server: [202.106.184.166]
Address: 202.106.184.166 *** 202.106.184.166 can't find amaxit.com.cn: Non-existent domain use your own domain name in the Mail System
Assume that your email server address is 61.176.1.120.
An A record has been created: mail.mydomain.com A 61.176.1.120. The MX record already exists.
If the MX record already exists and is found on a Domain Name Server, you need to contact your domain name service provider or the administrator of the Domain Name Server, modify the MX record as follows:
Your domain name in mx 10 mail.mydomain.com
The MX record does not exist.
There are two ways to determine the exact DNS resolution of your domain name, one is to check the relevant application materials you submitted when registering the domain name, get the application accepted at that time, and contact the application accepting organization, so that the relevant personnel of the other party can help you find out; the other is obtained through nslookup in WinNT, Win2000, or various Unix operating systems.
After finding your domain name server, please contact your domain name service provider or the administrator of the server to allow the Peer to add an MX record for you. The record format is as follows:
Your domain name in mx 10 mail.mydomain.com
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. Now there is a user in the browser to type 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 sends the IP address 1.1.1.1 of myhost.abc.com to 8.8.8.8. However, 8.8.8.8.8.8 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 TTL expires, the above process will be repeated. Each of the following causes may cause your resolution to fail. The DNS of the domain name is not set to the correct DNS as required. For your resolution settings, the DNS of the domain name must be ns1.dns.com & ns2.dns.com, or other DNS that has already pointed to the two DNS.
No resolution records have been set for the domain name. If you want to modify the DNS of the domain name, you need to go to the domain name management interface of the Registrar. The DNS has been modified at the Registrar. Why does the DNS check the old DNS?
DNS check is based on the current data of the DNS root server. It may take 12-72 hours for the Registrar to modify the DNS to reflect it on the root server. The resolution takes effect. 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 email forwarding. 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, to set 218.5.1.249 as the email server of whatis.cn, resolve mail.whatis.cn to 218.5.1.249 (fill in "mail" in the "host name" column, and select "A" as the "type ", fill in "218.5.1.249" in "IP Address/Host Name", and then press "add ")
Set the MX record of whatis.cn to mail (the "host name" column is left blank, select "MX" for "type", and enter "mail" for "IP Address/Host Name ", then press "add ")
Set 218.5.1.249 to allow @ whatis.cn emails to be received.
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 comply with your meaning. 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. For example, if a CNAME record "abc" is added under the whatis.cn domain to "123", then abc.whatis.cn indicates parsing with 123.whatis.cn.
Adding a CNAME record "abc" under the whatis.cn domain indicates "host.com.", then abc.whatis.cn indicates that it is parsed using host.com. Why is "Priority" always set to "0 "?
"Priority" is only valid for MX records. Priority is ignored for other types of records. |
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