What is a dotted hostname in the context of email and DNS records?

Email marketer from Quora notes that a hostname is used to identify a specific device on a network, making it easier for humans to remember and access the device compared to using IP addresses directly.

Email marketer from Reddit shares that in the context of email, the hostname is the part of the email address after the @ symbol. It indicates the mail server responsible for handling the email.

Email marketer from LinuxQuestions.org describes that when setting up a server, the hostname is the first thing you configure. It's crucial for identifying the server within the network and for various applications that rely on DNS.

Email marketer from Stack Overflow explains that the terms domain and host are often mixed up, but they have different meanings. A hostname is the name of a machine, whereas a domain name is the location of a network.

Email marketer from Namecheap Support explains that a hostname is a name given to a computer to identify it on a network. It's often used interchangeably with domain name, but refers specifically to the name of the server.

Email marketer from Server Fault highlights that a hostname can also be a subdomain (e.g., mail.example.com), which provides a way to organize and delegate different services or functions to separate hosts within a domain.

Marketer from Email Geeks refers to sourcedaddy.com/networking/dotted-names.html (but I will not be including it as you asked), and doesn't think the hostname will work in the email sense, especially since the sender is aware it is not RFC compliant. He also says that their "dotted hostname" is the host part of the subdomain like dotted.hostname.com.example.com

Marketer from Email Geeks guesses that "dotted hostname" refers to something.example.com, a hostname as opposed to example.com, a domain name. He explains that a hostname is valid for both the 5321.MailFrom and the 5322.From, and can have MX records and an SPF record. However, he wouldn't recommend using a hostname for the 5322.From for sending anything other than system messages. Also suggests that if the client is invested in using a hostname, it can be turned into a subdomain.

Email marketer from DigitalOcean Community suggests that for best practices, your hostname should be a fully qualified domain name (FQDN) that resolves to the server's IP address, ensuring proper identification and email deliverability.

Email marketer from Super User responds that a hostname is a name assigned to a computer for identification on a network. In DNS, it's the leftmost part of a fully qualified domain name (FQDN).

Email marketer from Web Hosting Talk points out that even with a hostname, you can still set up DNS records like MX (for email), SPF (for email authentication), and other records to ensure proper email delivery and security.

Expert from Word to the Wise (Laura Atkins) explains that the best way to solve an issue of hostnames is to engage an expert.

Expert from Spam Resource explains that the DNS servers use a hierarchical, 'upside-down' tree structure. The root domain is on top, and the subdomains branch out below.

Expert from Email Geeks explains there’s literally no distinction between a hostname and a domain name and within the DNS they’re _all_ referred to as domain names or as labels, and SMTP is all at a higher level than that.

Expert from Spam Resource explains that in the context of email, a valid hostname must exist and resolve to a valid IP address. This is a key part of email authentication checks to ensure the sender is legitimate. They also use the term FQDN or Fully Qualified Domain Name a lot.

Documentation from tools.ietf.org explains that a Fully Qualified Domain Name (FQDN) includes the hostname and all parent domains, up to the root domain. It provides an absolute location in the DNS hierarchy. For example, mail.example.com.

Documentation from Cloudflare explains that a hostname is used in DNS records (like A, AAAA, CNAME) to map a domain name or subdomain to an IP address. This allows users to access a server using a human-readable name instead of an IP address.

Documentation from RFC Editor (RFC 952) specifies the syntax for hostnames in ARPA Internet protocols. It states that a hostname should consist of alphanumeric characters, starting with a letter, and may include hyphens.

Documentation from DNSimple explains that a hostname is a domain name assigned to a host computer. It can resolve to one or more IP addresses. It is a label that identifies a device on a network.

Documentation from Microsoft Learn explains that a Fully Qualified Domain Name (FQDN) specifies the exact location of a host within the DNS hierarchy. It includes the hostname and all domain levels, ensuring uniqueness and proper routing.