These DNS records are going to help you set the grounds for extremely secure and safe email communication. So, let’s start with our short list.
A record
One of the most popular DNS records is the A record, also known as an Address record. It points a domain name to its corresponding IP address (IPv4 address). Its purpose is fundamental. In addition, it shows that the particular domain name is associated with that IP address. However, it does not direct the mail servers, and they wouldn’t know where they should send email messages.
What is a SMTP server and why to use it?
MX record
MX record, or Mail exchanger record, is one of the most popular DNS records. Its main purpose is to show which is the mail server responsible for receiving email messages for the particular domain name. It is important to note that, in case there is a mistake in the configuration of your MX record, or it does not exist at all for your domain name, you won’t be capable of receiving email messages. Therefore, if you desire to have proper receiving mail service, you should definitely set an MX record and be really careful.
PTR record
The Pointer record, or simply for short PTR record, is another essential type of DNS record for your email and email security. Its purpose is to link an IP address (IPv4 or IPv6) to its corresponding domain name. Its goal is absolutely the opposite compared to the A record. It is used to provide trust and confirmation that the particular domain name (hostname) is actually related to the specific IP address. Therefore, it is considered an essential part when you want to establish properly working outgoing mail servers. In case you do not have such a DNS record or you have made a mistake in the configuration of it, the emails you send are going to be marked as spam messages and rejected right away. That is something nobody wants. Therefore you should be aware and set everything correctly.
SPF record
The SPF (Sender Policy Framework) record is a simple TXT record that provides information with a list of all the IP addresses that are allowed to send an email message on behalf of your domain name. Thanks to it, the recipient’s mail server is able to check and verify that the email is actually coming from your domain. It helps prevent DNS spoofing and phishing attacks.
DKIM record
DKIM (DomainKeys Identified Mail) record is another TXT record that serves for email authentication. It allows the recipient’s server to check if the sender is actually the one that is claiming to be and prevent receiving a message from a forged sender. It is really valuable for detecting and stopping email spam and phishing.
Thanks to the provided encryption key and digital signature, it is able to verify that the message was not falsified or modified. Additionally, it improves the security of your email deliverability.
DMARC record
DMARC (Domain-based Message Authentication, Reporting, and Conformance) record is also a TXT Record published for a domain name. It regulates what happens if an email fails the authentication. Together with the SPF record and DKIM record, it sets strong email security.
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