Article Category: LAN Article Title: Glossary: DNS MX records CNAME record A record TTL Keywords: 0 author of the article: alonglee turn Article Source: http:? //Www.szgm.com.cn/landiy/Article_Show.asp ArticleID = 785 Published: 2004-7-16 13:59:00 What is a domain name resolution? Domain name parsing is the conversion process of domain names to IP addresses. The IP address is a digital address identified on the Internet. For the sake of simplicity, use the domain name instead of the IP address identification site address. The resolution of the domain name is done by the DNS server. What is a record? A (address) Record is used to specify the IP address record corresponding to the host name (or domain name). Users can point to the website server under this domain to their own Web Server. You can also set the secondary domain name of your domain name. What is MX record? Mail routing records, users can point the mail server under this domain to their Mail Server, and then manipulate all mailbox settings. You only need to fill in the IP address of your server online, you can transfer all your domain names to your own settings on the appropriate mail server. What is CNAME record? That is: an alias record. This record allows you to map multiple names to the same computer. It is usually used to provide a computer that provides both WWW and MAIL services. For example, there is a computer name "host.mydomain.com" (a record). It offers WWW and MAIL services, in order to facilitate user access services. Two alias (CNAME) can be set for the computer: WWW and MAIL. The full name of these two aliases is www.mydomain.com and "mail.mydomain.com". In fact, they all point to "Host.Mydomain.com". What is a TTL value? The TTL value is "Time to Live", which means that it indicates that DNS is recorded in the DNS server. To understand the TTL value, first look at the following example: Suppose, there is such a domain name myhost.abc.com (in fact, this is a DNS record, usually in the ABC.COM domain has a host) corresponding to a host) correspondence The IP address is 1.1.1.1, and its TTL is 10 minutes. This domain name or this record is stored on a DNS server named DNS.Abc.com. Now there is a user typing a address in the browser (also known as URL): http://myhost.abc.com; what happens when this happens? The visitor designated DNS server (or his ISP, Internet service provider, dynamic assignment to him) 8.8.8.8 will try to explain myhost.abc.com, of course 8.8.8.8 This DNS server is not included MyHost.abc.com This information has not been analyzed immediately, but after the recursive query of the global DNS, it will eventually be positioned to DNS.Abc.com This DNS server, DNS.abc.com This DNS server will Myhost.ABC. The corresponding IP address of the COM 1.1.1.1 tells 8.8.8.8 This DNS server, then tells the user results by 8.8.8.8. 8.8.8.8 In order to speed up the resolution of this record on myhost.abc.com, it will be reserved for a while, this is TTL time, and if the user has myhost.abc.com during this time. The resolution request of this record, it tells the user directly 1.1.1.1, which will repeat the above process when TTL expires.
