DNS

You might say

I bought a domain, so why do I still need to set up DNS? Help me point it to my server.

Connect a domain name to the service that should answerDNS translates a domain into records that direct browsers and other clients to a host, email service, or verification target. Changes may take time to spread because records are cached. Keep the required record type, name, value, and previous configuration clear before editing.
Know first
Domain
🌐BrowserSearch
vibeui.dev
→
📒DNS ResolverReturn record
76.223.54.1
→
🖥️Target serviceConnect to the returned
IP address

When to use it

  • Point a domain to a website
    A@76.223.54.1
    An A record points a name to an IPv4 address.
  • Configure a subdomain
    CNAMEwwwvibeui.dev
    A CNAME points one name to another domain.
  • Connect email service
    TTL 600Max cache: 10 min
  • Verify domain ownership
    $ dig vibeui.dev;; ANSWER: 76.223.54.1

When NOT to use it

  • Delete existing records without checking their purpose
    Awww → 76.223.54.1
    CNAMEwww → vibeui.dev
    A CNAME for the same name generally cannot coexist with an A record.
  • Expect every resolver to update immediately
    Changed to AChanged backMultiple changes
    Repeated changes before the cache expires make it hard to trace issues to one configuration.
  • Mix up the record name and destination
    TTL 86400Max cache: 1 day
    Old records may remain cached for a long time, so changes also take longer to converge.
  • Publish private server credentials as DNS values
    A76.223.54.12
    An incorrect address can send requests to the wrong service or make the site unreachable.
Anatomy
🌐Browser→📒DNS Server→A record
vibeui.dev → IP→76.223.54.1
The browser usually hands off the query to a recursive resolver; it checks the cache and, if necessary, queries the authoritative DNS
Server that keeps official records for domain names; recursive resolvers get cacheable answers from here
The line you registered in the console: A records the IP, CNAME records another domain name
The found house number is used by the browser to knock on the server's door.
Variants
A Record
A @ → 76.223.54.1
Domain names point to IPv4 addresses, most commonly used
CNAME
CNAME www → vibeui.dev
The domain name points to another domain name, commonly used in hosting
AAAA
AAAA @ → 2606:…:1
Domain name points to IPv6 address
TXT
TXT @ → "verify=8f2k…"
Used when verifying domain name ownership and configuring email addresses
Typical use cases
Website launch
DNS resolution · vibeui.dev
TypeHost RecordRecord ValueTTL
A@76.223.54.1600
CNAMEwwwvibeui.dev600
CNAMEblogvibeui.dev600
Subdomain setup
$ dig vibeui.dev
;; QUESTION SECTION:
;vibeui.dev.   IN  A
;; ANSWER SECTION:
vibeui.dev.  600  IN  A  76.223.54.1
;; Query time: 23 msec
Email records
Modify parsing record
TypeA
Record value
TTL Seconds; smaller TTL facilitates switching, but does not clear existing cache
Ownership verification
Migrate to a new server
Old: A @ → 76.223.54.1Deactivated
↓ Modify record value
New: A @ → 76.223.105.8Effective
Before the end of the old record caching, some users may still access the old server; confirm that the traffic has been migrated before closing the old service.
Further reading
DNSMDN ↗