Adding or changing a DNS record

Most external services — a shop platform, a mail provider, a Google verification — ask you to add a single record to your domain. This is what you need for that.

Which record for which purpose

• A — points your domain or a subdomain at the IP address of a server.
• CNAME — points one name at another name. Use it for subdomains that an external service manages itself. On the bare domain (without www) this is usually not possible.
• MX — decides where your email arrives. Entirely separate from where your website runs.
• TXT — free text. In practice for SPF, DKIM, DMARC and to prove a domain is yours.

How to add one

1. Go to wherever your DNS is managed: the party running your nameservers, not necessarily your registrar or your host.
2. Pick the record type the service tells you. Take it literally — a CNAME where an A is asked for does not work.
3. Fill in the name. For the domain itself that is usually an at sign or an empty field; for a subdomain only the part in front, so mail and not mail.yourdomain.be.
4. Paste the value exactly as you received it, without adding quotes and without spaces before or after.
5. Leave the TTL as it is, unless you know you will change it again soon.
6. Save and wait. A new record is usually visible within the hour; a changed record takes as long as the old TTL.

Where it usually goes wrong

• The name is entered too long. Most panels already append the domain; type it again and you end up with mail.yourdomain.be.yourdomain.be.
• Two SPF records. There may only be one. To allow a second service, add it to the existing record instead of putting a new one next to it — with two records the check fails for both.
• Checking too soon. Your own computer remembers the old answer. Test through an external DNS check rather than through your browser.