域名DNS邮件配置故障修复咨询

Hey there, let's work through fixing your email issue step by step—your setup has a clear mismatch that's likely causing the problem, so let's sort it out.

First, let's pinpoint the core issue: You mentioned your email is hosted on the server at x.x.x.x, but your current MX records are pointing to mx1-mx4.blabla.com instead of your own mail server. MX records tell the internet where to send emails addressed to your domain, so right now all incoming mail is trying to go to blabla's servers instead of yours. That's almost certainly why your email isn't working.

Here's what you need to do to fix this, while keeping your website at y.y.y.y as requested:

• Update your MX records

  • Delete all four existing MX records pointing to mx1.blabla.com through mx4.blabla.com.
  • Add a new MX record for example.com that points to your mail server's domain: mail.example.com (since you already have an A record linking mail.example.com to x.x.x.x). Set a priority value (lower numbers mean higher priority)—10 is a safe default. The record should look like this:

    MX    example.com    10    mail.example.com
    

• Fix your SPF record

  • Your current SPF record includes spf.blabla.com, which is meant for blabla's mail servers. Since you're using your own server at x.x.x.x, you need to update this to authorize your server instead. Change the TXT record for example.com to:

    TXT   example.com    v=spf1 ip4:x.x.x.x -all
    

  • If you ever add other legitimate sources that send email from your domain (like a marketing tool), you can include those in the SPF later, but start with just your mail server IP first.

• Add optional (but highly recommended) DKIM and DMARC records

  • DKIM: If your mail server supports DKIM, generate a public/private key pair. Add a TXT record to your DNS with the name dkim._domainkey.example.com (you can use a different selector like default if you prefer) and the value as your public key string, formatted like:

    TXT   dkim._domainkey.example.com    v=DKIM1; k=rsa; p=YOUR_PUBLIC_KEY_HERE
    

    This helps email providers verify that emails claiming to be from your domain are actually sent by your server, reducing the chance of them being marked as spam.
  • DMARC: Add a TXT record named _dmarc.example.com with a value like:

    TXT   _dmarc.example.com    v=DMARC1; p=none; sp=none; rua=mailto:dmarc@example.com
    

    This starts in monitoring mode (p=none) so you can receive reports about email activity for your domain. Once you're confident your setup is working, you can switch to p=quarantine or p=reject to block unauthenticated emails pretending to be from your domain.

• Wait for DNS propagation and test

  • DNS changes can take anywhere from a few minutes to 24 hours to take effect across the internet, depending on the TTL (time-to-live) settings of your old records. You can use tools like dig or nslookup to check if the new records are live—for example, run dig example.com MX to see if your new MX record shows up.
  • Once propagated, send test emails to an external address (like Gmail or Outlook) and also send emails from an external address to your @example.com account. If issues persist, check your mail server's logs for error messages (like connection refusals or authentication failures) to narrow down the problem.

Remember, you don't need to touch the A record for example.com pointing to y.y.y.y—that's already set correctly for your website.

备注：内容来源于stack exchange，提问作者Abdusalam Ben Haj