DiG DNS lookup

DNS record types

• A / AAAA — the IPv4 / IPv6 address of a name.
• CNAME — an alias that points one name at another (e.g. www to the main domain or a hosting platform).
• MX — the mail servers for the domain; the lowest priority number is tried first.
• TXT — free text, used for SPF, DKIM, DMARC and the verification codes services like Microsoft 365 or Google ask you to add.
• NS — the authoritative name servers for the domain.
• SOA — the zone’s primary server, admin contact, serial number and timers.
• SRV — where a specific service lives, for example SIP or Microsoft Teams/Skype records.
• ANY — asks for everything; many DNS servers now answer ANY with only a minimal reply (RFC 8482), so query types one at a time for a full picture.

TTL and DNS changes

The TTL (time to live) is how many seconds a resolver may keep an answer in its cache. After you change a record, some people keep getting the old value until the old TTL runs out. Before a planned change — moving a website or mail — lower the TTL to 300 seconds a day in advance, and raise it again afterwards.

Related tools

For mail servers with their IPs, use MX lookup. For a full check of a domain’s DNS setup, use DNS health check; for email security records, the Domain trust report.