The A DNS record, also known as the Address record, is one of the fundamental components of the Domain Name System (DNS). It plays a crucial role in mapping domain names to their corresponding IP addresses. However, it is important to note that the A DNS record does not contain the name to IP address mapping for all the hosts within a domain.
The A DNS record is specific to an individual host within a domain. It associates a domain name with the IP address of a particular host. When a user enters a domain name in their web browser, the DNS resolver queries the DNS system to retrieve the IP address associated with that domain name. The A DNS record is one of the responses that the resolver can receive.
To illustrate this concept, let's consider an example. Suppose we have a domain called example.com, and within that domain, we have two hosts: host1.example.com and host2.example.com. Each host will have its own A DNS record. The A DNS record for host1.example.com will contain the mapping of host1.example.com to its corresponding IP address, let's say 192.168.0.1. Similarly, the A DNS record for host2.example.com will contain the mapping of host2.example.com to its corresponding IP address, let's say 192.168.0.2.
In this scenario, if a user wants to access host1.example.com, their DNS resolver will query the DNS system for the IP address associated with host1.example.com. The DNS resolver will receive the A DNS record for host1.example.com, which contains the mapping to 192.168.0.1. The resolver will then use this IP address to establish a connection with the desired host.
It is worth mentioning that the DNS system also supports other types of records, such as CNAME (Canonical Name) records, which are used for aliasing one domain name to another, and MX (Mail Exchanger) records, which are used for routing email. These records serve different purposes and are not directly related to the A DNS record.
The A DNS record is responsible for mapping a specific domain name to its corresponding IP address for an individual host within a domain. It does not contain the name to IP address mapping for all the hosts within a domain.
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- Field: Cybersecurity
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