How to Setup MX Record in Cloudflare

Your domain uses Cloudflare DNS (david.ns.cloudflare.com). To route mail to your ISPConfig server, you must add two specific records in your Cloudflare dashboard.
  1. Log into Cloudflare and open the DNS settings for example.com.
  2. Add an A Record for your mail subdomain:
    • Type: A
    • Name: mail
    • IPv4 address: Your ISPConfig server's public IP address
    • Proxy status: DNS Only (Grey Cloud) ⚠️ Crucial: Do not use the orange cloud for the mail subdomain, or mail delivery will fail.
  3. Add the MX Record:
    • Type: MX
    • Name: @ (or leave it as example.com)
    • Mail server: mail.example.com
    • Priority: 10
 
How to Verify the Fix
Once you save those records in Cloudflare, rerun your dig command from your local machine using WSL:
dig mx example.com +short

1. Verify Catch-All Configuration in ISPConfig
In ISPConfig, a catch-all is explicitly created as an Email Forwarding rule, not inside the mailbox configuration itself.
  1. Log into your ISPConfig Control Panel.
  2. Go to Email > Email Accounts > Catchall.
  3. Click Add New Catchall.
  4. Configure the settings exactly like this:
    • Domain: Select example.com from the dropdown list.
    • Destination Email: Type the exact full address of the mailbox where you want the mail delivered (e.g., [email protected]).
    • Active: Ensure this box is checked.
  5. Click Save and wait 1–2 minutes for ISPConfig to write the changes to the system.
 
2. Check the Mail Logs for Catch-All Failures
If you have already configured the catch-all but it still fails, send a test email to a fake address (like [email protected]) and stream your log file immediately:
sudo tail -n 50 /var/log/mail.log
 

 

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