Practice next
Read the concept, then use a quiz, builder or checklist to make it stick.
Quick reference
| Area | Commands or meaning |
|---|---|
| A | Hostname to IPv4 address |
| AAAA | Hostname to IPv6 address |
| CNAME | Alias to another hostname |
| MX | Mail exchanger for a domain |
| TXT | Text data for SPF, DKIM, DMARC and verification |
| NS | Authoritative nameservers |
| TTL | How long answers may be cached |
How to use it
Do not memorise every flag. Memorise the situation, the first command to run, and how to check whether the output makes sense.
Practice prompt
Pick three entries from the table and create a tiny lab. For example, make test files, search them, change permissions, and explain what changed.