Learn how MX records work, how to check them, and how to troubleshoot missing or incorrect mail exchanger records.
- Check mail routing quickly
- Spot missing or wrong MX records
- Understand priorities and provider changes
What MX records do
MX records tell other mail servers where to deliver email for a domain. They include a mail server hostname and a priority value. Lower priority numbers are tried first. The mail server hostname should then resolve to an IP address using A or AAAA records.
How to check MX records
Use the DNSNow lookup tool with the MX type, or run dig example.com MX from a terminal. If no MX records exist, some systems may fall back to the domain’s A record, but proper mail hosting should normally have explicit MX records.
Common MX mistakes
Common mistakes include pointing MX records directly at an IP address, leaving old provider MX records in place, deleting the provider’s verification TXT records or editing the wrong DNS zone. Email migrations deserve a checklist, not vibes.
What to check next
After MX, check SPF, DKIM and DMARC records. These do not usually decide where email is delivered, but they strongly affect whether mail is trusted, accepted or marked as suspicious.
Quick commands to try
dig example.com Adig example.com MX +shorthost -t TXT example.comPractise the command line side
DNSNow gives you quick web checks. For hands-on Linux command practice, use CommandLineQuiz dig Command Builder, the Linux Troubleshooting Hub and the Bash Scripting Hub.
FAQs
Can an MX record point to an IP address?
No. MX records should point to a hostname, and that hostname should resolve to an address.
What does MX priority mean?
Lower numbers have higher priority. Mail servers try lower priority MX records first.
Do I need MX records to send email?
MX records are mainly for receiving email. Sending reputation and authentication involve SPF, DKIM, DMARC and the sending mail server configuration.