What is Round-Robin DNS?
Round-Robin DNS is a mechanism for administrating the incoming traffic.
This technique is based on the time of arrival of the user request and the actual number of servers that you have. Simply you create several A or AAAA records with different IP addresses (IPv4 and IPv6) that correspond to the multiple servers. Each one of them stores a duplicate of the information for your website. So, whenever a user requests your domain name, the authoritative name server, storing the A or AAAA records, is going to provide the next in rotation turn A or AAAA records from those you created. The users are going to be automatically directed when they are desire to reach your website. The exact moment when they reach your DNS name server is important for the precise order.