


What is the specific difference between CNAME and A during domain name resolution?
What is the specific difference between CNAME and A during domain name resolution? I only know that CNAME resolution is required when accelerating website domain names. Why is this?
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What is the specific difference between CNAME and A during domain name resolution? I only know that CNAME resolution is required when accelerating website domain names. Why is this?
A record:
To point the domain name to an IPv4 address (for example: 10.10.10.10), you need to add an A record
CNAME record:
If you point the domain name to a domain name to achieve the same access effect as the pointed domain name, you need to add a CNAME record
MX records:
Establish an email service, which will point to the mail server address. MX records need to be set
NS records:
Domain name resolution server records. If you want to specify a subdomain name server for resolution, you need to set NS records
TXT records:
Can be filled in arbitrarily (can be empty), usually used as SPF record (anti-spam) using
AAAA record:
Point the host name (or domain name) to an IPv6 address (for example: ff03:0:0:0:0: 0:0:c1), you need to add an AAAA record
SRV record:
records which computer provides which service. The format is: the name of the service. The type of protocol (for example: _example-server._tcp)
Explicit URL:
Point the domain name to an http(s) protocol address. When accessing the domain name, it will automatically jump to the target address (for example: After www.net.cn is explicitly forwarded to www.hichina.com, when accessing www.net.cn, the address displayed in the address bar is: www.hichina.com).
Implicit URL:
Similar to explicit URL, but implicit forwarding will hide the real target address (for example: after implicitly forwarding www.net.cn to www.hichina.com, when accessing www.net.cn, The address displayed in the address bar is still: www.net.cn).
This is the introduction to Alibaba Cloud
Some service providers have many virtual hosts on one server. I guess that in order to facilitate customers to bind domain names, they use CNAME
The difference is all mentioned above.
As for the website acceleration service you mentioned, it should refer to CDN. The CDN service provider provides you with a domain name.
For example, your domain name is www.mstiantang.com
, and you have done a CNAME , resolve to www.cdn.com
.
In this way, when you visit www.mstiantang.com
, you will visit www.cdn.com
, and an intelligent load system is deployed on www.cdn.com
, According to the information of the accessed client, it is automatically loaded to a node with the smallest access cost for the client, so as to achieve acceleration.
As for why it is CNAME instead of A, it is because it is convenient. He does not have to change the server IP and has to remind you to add an A record. It has more initiative.

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