DNS propagation refers to the amount of time that is required for updating the latest DNS data (DNS records) completely through the entire network of servers on the web. When you make modifications and adjustments to your DNS records, they are not immediate. The reason for that is because the various nameservers keep the DNS data (DNS records) inside their cache memory for a particular amount of time before they refresh. So while your domain won’t experience any downtime from appropriately planned DNS record modifications, some of the users could still be served a cached version of your website. That will continue until the DNS propagation is completed. Learn more additional information about DNS propagation!
Reverse DNS, which is also commonly known as rDNS, is used to show which is the domain name corresponding to an IP address (IPv4 or IPv6). It is actually exactly the opposite process of the usual Forward DNS, where the purpose is to find the matching IP address for a domain name.
For achieving its goals and completing the process, rDNS requires using PTR records. rDNS is typically implemented to identify and validate that the IP address actually belongs to the specific domain name. That way, it is easier to avoid scams and spam emails. Read more about rDNS!
The MX record is a DNS record where MX stands for mail exchange. It serves for directing and pointing to a mail server. The MX record provides information about how the email messages should be routed. In addition, it indicates which is the accountable server for receiving emails for a particular domain name.
The mail exchange record includes the hostname of the server that handles the emails for a domain and a prioritization code. With it, you could set different priority numbers. That way, you are able to separate the load among more than one server and provide redundancy. Find out more details about the MX record!