As websites are increasing, people trying to increase the security of their websites by adding SSL either as paid or free. Most small scale sites have Cloudflare as their SSL protection.
But when you will add CloudFlare to your main domain, it only points the main domain but not any subdomain.
So, when you will try to open the subdomain, you will see the error,
"server not found"
4. then add a CNAME record
Name = your subdomain
ipv4 = your main domain name
5. Now, just wait for 2-4 hours. And that's it.
Some Common Definitions
A record (Address Record) points a domain or subdomain to an IP address. For example, you can use it for store.website.com or blog.website.com and point it to where you have your store. This is a common practice for people who use Amazon, eBay, Tumblr, etc.
DNS records are used to control the location of a resource on the Internet. As an example, an A Record is used to point a logical domain name, such as "google.com", to the IP address of Google's hosting server, "220.127.116.11".
These records point traffic from example.com (indicated by @) and ftp.example.com to the IP address 18.104.22.168. They also point localhost.example.com to the server that the domain is hosted on. This allows the end user to type in a human-readable domain, while the computer can continue to work with numbers.
CNAME records are another commonly used type of DNS entry and are used to point a domain or subdomain to another hostname.
A Canonical Name record is a type of resource record in the Domain Name System which maps one domain name to another This can prove convenient when running multiple services from a single IP address.