MX Lookup

The MX record or the mail exchange record is the type of DNS record set up through the hosting provider to set up the email servers for that domain.

At the end of 2020, there were almost 4.66 billion internet users in the world. The majority of them are connected to the internet 24/7 through their digital devices.

Currently, there are almost 2 billion websites on the internet. When we enter any URL in our browser search bar, we instantly land on that specific URL. From the total number of internet users and websites, you can easily judge the number of internet searches done on the internet daily.

However, no one can get the correct numbers about DNS queries, but that would be in trillions.

All that system works so smoothly, just because of the DNS (Domain Name System), that routes the traffic to the correct destination.

The DNS servers contain the DNS records. Each domain has its DNS records that are the mapping files to route the user to that domain's particular service.

The stat shows there are above 3.99 billion email users globally, and with time they will increase.

The DNS MX record is a DNS record that routes the email to the correct email server.

The MX record tells which mail server is responsible for receiving the emails related to a particular domain and sending an email message to a route following the Simple Mail Transfer Protocol.

The process of querying the MX record is simple: when the user sends an email address. The MTA (Message Transfer Agent) software starts sending the query to identify the MX record. If the MX record exists, it establishes an SMTP (Simple Mail Transfer Protocol) connection with those mail servers as per their priority hierarchy. Test your SMTP connection.

Suppose there are two MX records for the domain example.com.

• 10 mail1.example.com
• 20 mail2.example.com

The number at the start represents the priority. The lower the number, the more priority it gains. In the above case, the server tries mail1 when attempting to deliver an email. If it fails, then it tries mail2 to deliver an email.

Example MX Record

An example MX record for the domain example.com looks like the following:

Here,

• MX is the record type.
• example.com is the domain of the record.
• 10 & 20 are the priority of the record. The lower the value, the more priority it gets.
• mail1.example.com & mail2.example.com are the values of the record.
• 3600 is the TTL (time to live) of the record in seconds. TTL is the time that tells the DNS resolver how long cache the DNS query before requesting a new one.

In the MX record, the value represents the priority. The lower the value, the more priority that the mail server will receive in delivering the mail. The MX record backup is another MX record for the domain with a higher priority value.

In the above case, the server tries mail1 when attempting to deliver an email. If it fails, then it tries mail2 to deliver an email.

However, to spread the load across many mail servers, a single mail server cannot manage it. The multiple MX records with the same priority value can process the email where one is picked randomly.

An example MX record with a combination of MX record backup and load balanced for the domain example.com looks like the following:

In this example, the mail servers mail1.example.com and mail2.example.com will get an equal chance to handle email processing. If both fail to respond, then the mail server at mail3.example.com will take processing the email.

The MX records contain the hostname that manages the mail for the particular domain. No MX record can point to an IP address. Therefore, the mail server cannot accept it if the MX record is the IP address. More importantly, according to the RFC documents, pointing the MX record to the CNAME alias is forbidden.

Multiple MX records can be defined for the domain, each with its priority value where the lowest number is given the highest priority value. The server tries the mail server with the top priority record to deliver an email. If it fails, then it tries the mail server next in the priority record to deliver an email.

However, if different MX records have the same priority number, then one is picked randomly.

To find the Mailrservers of the domain or perform the Mailserver Lookup or MX Lookup. Do the following steps.

• Open the MX Lookup tool.
• Enter the domain name in the space mentioned for that purpose.
• Click on the "CHECK NOW" button to get the mail servers of the entered domain name.
• The tool will perform the Mailserver lookup and provides you the results.
• The result will include the type of record, domain name, priority, MX (mail servers), and TTL (time to live).