Why It Matters
Your DNS records are the foundation of your entire email setup. Get them wrong, and your emails won't arrive, your authentication will fail, and your domain will look suspicious to every receiving server on the internet. DNS isn't glamorous, but misconfigured DNS records are behind a huge percentage of deliverability issues.
How It Works
DNS translates domain names into machine-readable instructions. For email, the key record types are:
- MX records — tell the world which servers accept email for your domain. Without them, nobody can send you email.
- TXT records — hold your SPF policy, DKIM public keys, and DMARC configuration. They're the backbone of authentication.
- CNAME records — often used to point subdomains to your email provider's infrastructure (like DKIM signing domains or tracking domains).
- A/AAAA records — map domain names to IP addresses, used for web hosting and sometimes mail server configuration.
DNS changes propagate across the internet over time (typically 1-48 hours, depending on TTL settings). This is why email platform setup guides tell you to wait before testing.
Quick Tips
- Use low TTL values (300 seconds) when you're making changes so you can iterate quickly. Raise them back to 3600+ once everything's stable.
- Keep a documented inventory of every DNS record related to email. When you switch providers, you'll need to update all of them.
- Use MXToolbox or Google's Dig tool to verify your records look correct from the outside — what you see in your registrar panel and what the world sees aren't always the same.