What is MX Record?
An MX (Mail Exchanger) record is a DNS record that specifies which mail servers are responsible for receiving email for your domain and their priority order.
An MX (Mail Exchanger) record tells the world where to deliver email for your domain. When someone sends an email to [email protected], their mail server looks up your MX records to find out which server should receive the message.
MX records have two components:
1. **Priority** (preference value): A number indicating which server to try first. Lower numbers = higher priority. If your primary server (priority 10) is unavailable, mail is sent to the backup (priority 20).
2. **Mail server hostname**: The domain name of the server that handles incoming email (e.g., mail.yourdomain.com or aspmx.l.google.com for Google Workspace).
A typical MX setup looks like: ``` yourdomain.com. MX 10 mail1.yourdomain.com. yourdomain.com. MX 20 mail2.yourdomain.com. ```
MX records are essential for receiving email but also affect sender reputation. Some mail servers check that your sending domain has valid MX records as a basic legitimacy check.
Why MX Record Matters
Without correct MX records, you cannot receive email at your domain—messages will bounce back to senders. This affects everything from customer support to password resets to business communications. MX misconfiguration is one of the most common causes of email problems, especially after domain transfers or email provider migrations. Understanding MX records helps you troubleshoot delivery issues and configure redundancy for critical business email.
How Ark Handles MX Record
Ark focuses on sending email, so you don't configure MX records with us—those point to where you receive email. However, having valid MX records for your sending domain signals legitimacy to receiving servers. When you add a domain to Ark, we verify your DNS is properly configured, including checking that your domain has working MX records as part of our domain health checks.
Frequently Asked Questions
Does MX priority 10 or 20 get tried first?
Lower numbers have higher priority. MX 10 is tried before MX 20. Think of it like a ranked list: 1st choice (10), 2nd choice (20), etc. If the first server fails, the sender tries the next one in order.
How many MX records should I have?
At least two for redundancy. If your primary mail server goes down, the backup can still receive email. Most organizations have 2-3 MX records. Google Workspace, for example, provides 5 MX records for redundancy.
How long do MX record changes take to work?
DNS propagation typically takes a few hours but can take up to 48-72 hours depending on TTL (Time To Live) settings. During migration, keep both old and new MX records active until propagation completes.
Do I need MX records if I only send email?
If you're only sending (like a notification-only system), MX records aren't strictly required. However, having valid MX records adds legitimacy—some spam filters check for them. At minimum, set up MX records pointing to a server that accepts mail, even if you don't actively use incoming email.
Can MX records point to an IP address?
No, MX records must point to a hostname (domain name), not an IP address directly. If you need to point to a specific server, create an A record for a hostname (like mail.yourdomain.com) and point your MX to that hostname.
Why is my email bouncing after changing MX records?
Most likely DNS hasn't fully propagated yet, or there's a configuration issue with the new mail server. Check that the new server is ready to accept mail and that MX records are correctly formatted. Use MX lookup tools to verify what DNS is returning.
Related Terms
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