DNS Troubleshooting for Website Owners

DNS explained without making your eyes glaze over.

DNS problems can make a perfectly healthy website look broken. Before changing hosting settings or blaming WordPress, check whether the domain is pointing to the right place.

Common DNS records

• A record: points a hostname to an IPv4 address.
• AAAA record: points a hostname to an IPv6 address.
• CNAME: points one hostname to another hostname.
• MX: controls where email is delivered.
• TXT: often used for SPF, DKIM, DMARC and verification records.

Useful checks

dig example.com
dig www.example.com
dig MX example.com
dig TXT example.com

If you do not want to use the terminal, run DNS lookups through DNSNow.

When to suspect DNS

Suspect DNS when one person sees the new site and another sees the old one, email suddenly stops delivering, or a domain works with one network but not another.

To practise DNS commands, try the dig command builder on CommandLineQuiz.