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NET-C0066 · IP & Internet Intelligence

WHOIS vs RDAP

Look up one name or address you are allowed to hold, and know whether the answer came from WHOIS or RDAP.

Updated 25 October 2026 · Comparison

This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.

What this hour is for

WHOIS and RDAP both describe registration data. RDAP is the structured successor. The tools query one object you type. They do not crawl a registry and they do not harvest contacts.

The record is about the registration, not about the person using an address this hour. Use it to confirm a prefix or a domain you operate, or a single object tied to a ticket. Do not build a contact list.

A missing record is a result. It is not a reason to probe the address. Privacy redaction in a record is expected. Do not try to defeat it.

The change you can finish

Apply nothing during the writing of the note. When the lab window opens, it is one change on the device named in the ticket. Read the draft, then the device, then decide.

Rollback is the file or the revision you saved first. You do not invent a rollback after the only copy is gone.

  1. Type one name or prefix you may hold.
  2. Read WHOIS or RDAP.
  3. Write the registrar or the network.
  4. Do not collect contacts.
  5. Do not probe the object.
  6. Stop.

Mistakes that outlive the command

WHOIS vs RDAP goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.

Decisions to write down

One decision for WHOIS vs RDAP: One object was queried. The source is named. Contacts were not harvested. Redaction was left alone. And no probe followed.

Checks before you call it done

Confirm this before you call the change done: The object is in the ticket. WHOIS or RDAP is named. No contact list exists. No probe was run. And the next step is plan, not a scan. If one of those fails, stop.

SourceShapeUse it for
WHOISText that varies by registryA single registration you may read
RDAPStructured dataThe same question, one object

Before you leave the device

WHOIS vs RDAP ends when the hostname on the device matches the hostname in the ticket. If it does not, you are on the wrong box. Stop. A command that succeeded on the wrong box is not progress.

The draft stays a draft until a person has read the names in it. A generator does not log into the device and does not know which interface is the uplink. You delete a line that names a device, a zone, or a prefix you did not write down.

0.0.0.0/0 is not kept because a sample included it. A source you can say is the source you keep. 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. They belong in the note. They are not prefixes you type onto a production device because they appeared in a draft.

prompt-for-this is a reminder that a secret is missing. It is not a password, a key, a community string, or a pre-shared key you save in the ticket or in git. The real secret stays in the store.

One change is the window. A VLAN and a routing protocol and a VPN do not share it. If two things move and the result is wrong, you will not know which one did it. The next feature waits for its own page.

If the same step fails twice, stop for the day. The failure is the result. Adding a forum command beside a half-applied config produces a device nobody can rebuild. Restore the copy you took first.

A second person reads the device name and the change aloud. If they cannot find them in the ticket, the note is not done. Silence is not agreement. Then leave the device alone.

This page is a planning guide. It is not a vendor manual, not an official standard, and not a permission to touch a network you do not administer. The pillar guide owns the wider design. This page owns one lab proof.

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