MX Record Lookup

What is MX Record in DNS?

An MX record, otherwise known as a "mail exchanger" record, is a type of DNS record that redirects emails to their respective mail server. The MX record holds the email domain that SMTP (Simple Mail Transfer Protocol) takes to route the emails. Therefore, it is essential to note that the MX record must be a domain name.

How Does MX Record Work?

The MX record provides a path for the email servers to direct the emails sent. For example, when an email server sends an email to the recipient, the email server looks up the respective MX record associated with the recipient's domain. The email server then uses this information to connect with the individual recipient's email server to deliver the email successfully.

According to RFC 2181, an MX record must only point to an email server's A record or AAAA record and cannot point to a CNAME, even though the CNAME may point to the email server's A record or AAAA record.

What is MX Record Used For?

The MX record acts as a map to identify the email server associated with the domain, and all senders may look up the record using a public/private DNS server.

Typically MX records are publicly available so that any email server attempting to send emails can look up the record to send emails. However, in certain instances, the MX record may only be accessible via private links or only internally to restrict the visibility of specific hosts to certain email servers.

MX Record Example & Anatomy

An MX record holds key parameters such as the domain name, TTL (Time-to-live), priority, and value to provide the necessary information for email routing.

1. The domain parameter represents the domain that the MX record belongs to
2. The priority parameter represents the mail server priority if more than one MX record is published.
3. The value parameter contains the email server's A record or AAAA record value.
4. The TTL parameter represents the time after which the email server must recheck the DNS record for any changes or collect new DNS information. If you are assigning a high TTL value to a record, you must ensure that the record wouldn't change regularly.

MX Record Check - How This Tool Works

This tool performs an MX lookup by using public DNS servers to locate the MX record of a particular domain.

The MX lookup relies on the availability of the DNS record on the public DNS servers. However, there may be instances where an MX record becomes unavailable, typically due to no MX record publication for the respective domain or the newly published record's worldwide propagation has not yet taken place.

FAQs

1 - What is MX in nslookup?

nslookup is a command available on most operating systems that allows users to query DNS information. This command will enable users to specify the DNS server, thus allowing them to look up internal or public DNS servers.

The nslookup function gathers all DNS entities published for a specific domain and includes the MX record within its output.

2 - What is MX verification?

MX verification is validating the MX record to ensure that it is specified appropriately without any issues.

This process includes verifying the parameters within the MX record and checking if the domain name and the actual MX value is fully-functional. It may be verified manually by obtaining the information from the email server administrator or simply ensuring that an email delivers successfully to the recipient.

It is also essential to ensure that the A record or AAAA record pointing to the email server is not blocklisted in any way since this can cause issues during the email delivery process.

3 - How do I know if my MX record is correct?

The easiest method of knowing if your MX records are working is by checking if you can receive emails from other senders that do not belong to your domain. If the delivery of the emails fails, you may need to go through the following troubleshooting steps and resolve the fault.

1. It would help if you verified that the MX records set are according to the specifications of the email service provider. For example, Microsoft and Google are two of the most popular email service providers for enterprises, and they have separate guides to set up MX records.
2. Suppose you have hosted your web domain in a different hosting service such as Zoho or GoDaddy. In that case, you may also need to verify within the administration console to ensure that all the records set are according to the email service provider's specifications.
3. The final step is to verify and approve the changes within the respective administration consoles.

4 - How to nslookup MX record?

To use nslookup to fetch the MX record of any domain, you need to configure the nslookup function only to filter the MX records of a domain by following the steps below.

1. You may use the operating system's "terminal" or "command prompt" to access the nslookup function._nslookup Using Windows Command Prompt_
2. Use the server command to set the preferred DNS server.
3. Set the record type as MX using the _set type=mx_ command.
4. Lookup the MX record of a specific domain by entering the domain name.

5 - Is an MX record required?

Yes, to receive emails, an MX record is required. The MX record holds the routing information necessary for a sender to send emails to an email server, and without an MX record, the emails would not have a valid route to follow.

Even though the RFC 5321 standard makes it optional for an email sender to have an MX record, it is a common standard that all domains that send and receive emails have an MX because most email servers reject emails originating from a domain without an MX record.

6 - Where can I find my MX records?

The domain's MX records are within the DNS server or web hosting provider. If your email service provider differs from your web hosting provider, these records will also be within the email service provider.