Using this table
Filter by type or keyword, spf, reverse, mail. The list covers what appears in real zones and real interview questions, rather than the full IANA registry of historical types.
The rules that cause tickets
Three restrictions explain most DNS misconfiguration. A CNAME excludes all other data at the same name, so the zone apex, which must hold SOA and NS records, cannot be a CNAME; that's why example.com pointing at a load balancer hostname needs a provider ALIAS or the newer HTTPS record. MX and NS must target hostnames with A/AAAA records, never IPs and never CNAMEs (it often works, but it violates the RFC and some resolvers care). And TTLs are promises: a 24-hour TTL means yesterday's value can be served for a day after you change it, lower the TTL before a migration, not during the outage.
Email lives in TXT
Deliverability is now effectively mandatory DNS work: an SPF record listing permitted senders, a DKIM public key under selector._domainkey, and a DMARC policy at _dmarc telling receivers what to do on failure. Missing any of the three lands mail in spam at the large providers. Verify with dig TXT example.com, dig TXT _dmarc.example.com, and remember SPF has a hard limit of 10 DNS lookups, exceeding it via nested includes silently breaks enforcement.