WHOIS data

Looking up a domain name's data in the .lu WHOIS database using a command line.

A WHOIS search, which looks up certain data for a domain name at any point its life cycle in the .lu registration base, can be accessed with a protocol applied specially by the .lu registry. Viewing the data is subject to the same restrictions as a WHOIS web search.

What data are transmitted by the WHOIS?  

A WHOIS search provides basic information about the domain name:

  • whether it is available for registration

  • its status - active or reserved - meaning that it was registered with or without name servers

  • the nature of its owner (professional or individual)

  • the registrar with which it was registered

  • its DNS name servers

  • whether it is currently being deactivated by its managing registrar or in quarantine and thus cannot be registered or modified

How do you query the WHOIS?  

This service is provided by server whois.dns.lu on port TCP 43, according to the technical reference document RFC3912 "WHOIS Protocol Specification" published by the Internet Engineering Task Force (IETF).

The reply sent by the server is encoded using the ISO-8859-1 standard in the following command lines:

Response line

 Meaning
domainname

Domain name covered by the query
domaintype

Status of the domain name, coded using the following values: 

  • ‘FREE’ if the domain name is available to be registered,  
  • ‘ACTIVE’ if the domain name is registered and active, 
  • ‘RESERVED’ if the domain name is registered and reserved.  

RESERVED status may, in some cases, have a suffix attached:

  • ‘ON HOLD’ if the domain name is being deactivated by its managing registrar.
  • ‘PENDING_DELETE’, if the name is in quarantine.
nserver

Names of servers to which delegation is assigned for the domain name, including their type of IP address (IPv4 or IPv6).
ownertype

Type of domain name owner:  

  • ‘ORGANISATION’ for an institution or company,  
  • ‘PRIVATE’ for a private person.
org-country

Country of origin of the domain name's owner, using international standard ISO 3166 country codes.
registrar-name

Name of the registrar with which the domain name is registered.
registrar-email

Email address of the registrar with which the domain name is registered.
registrar-url

URL of the registrar with which the domain name is registered.
registrar-country

Country of the registrar with which the domain name is registered.

Access to the WHOIS search is also provided by the web form page.

WHOIS restrictions  

  • The number of queries per source IP address is restricted, with a waiting period that doubles with each excess query.

  • If you've hit this restriction, wait for as long as stated in the reply, or you will have to wait even longer.

WHOIS is not meant to be queried to check the availability of a large number of domain names. Accredited registrars that want to perform mass checks must use the EPP command 'domain:check' from the EPP server.

Related FAQs

My registrar is accredited for .lu; how can I check whether a domain name is available?

To find out if a domain name is available, including domains in quarantine or those pending creation, use the EPP command ‘domain:check’ from the EPP server.

  • If the domain name is not available, the reason why it isn't is stated.
  • If the domain name is already registered, run the command ‘domain:info’ to learn both which registrar it is registered at, and which ‘TransferProhibited’ or ‘TradeProhibited’ restriction(s) apply.

You can also use the DAS, which operates on port 4343, but then you won't have access to the domain names in quarantine, or pending creation.

Why can't a domain unknown to WHOIS be registered?

You are trying to register a domain name listed as temporarily unavailable or in quarantine. To determine which exact case you're dealing with, send the EPP command ‘domain:check’ to the EPP server and check the ‘reason’ field.

I'm using WHOIS and I was blocked due to a large number of queries, why was this?

The number of queries per unit of time is limited for WHOIS. The service is intended for end users and is not meant to be queried by registrars that need to verify a large quantity of domain names. If that applies to you, see the question ‘My registrar is accredited for .lu; how can I check whether a domain name is available?’.

DAS data

Verify a domain name's availability from the DAS using a command line.

The DAS (Domain Availability Service) enables accredited .lu registrars to automatically verify the availability of a .lu domain name, with no limitation on the number of queries.

What data are transmitted by the DAS?  

The DAS has a purely informative role and enables you to find out whether: 

  • the domain name is registered,

  • the domain name is activated or reserved, meaning registered with or without a server name.  

How do you query the DAS?

The DAS is provided by the server whois.dns.lu on the port TCP 4343.

1. To send a query, enter the command GET followed by '1.0', and the domain name in lowercase, separating these elements with a space. Send the command with a line break (\r\n)

Example:

GET 1.0 domain.lu

2. The response from the server can be read in 3 main lines: 

Response line Meaning
%% RC

Status of the request's result, coded using the following values:

  • ‘n’ if the result has an error. (This is often a syntax error in the query. Check and fix the query. If the error persists, contact the .lu registry). 
  • ‘0’ if the request was successful. 
Domainname

Domain name covered by the query.
Status

Status of the domain name, coded using the following values:

  • 'FREE' if the domain name is not registered,
  • ‘ACTIVE’ if the domain name is registered and active,  
  • ‘RESERVED’ if the domain name is registered and reserved.

DAS restrictions

Domain names in IDN format are rejected by the DAS. They must be converted into an ASCII domain name, represented as 'xn--', before being encoded in the query.  

A DAS search offers only limited information. To access domain names in quarantine or those pending creation, a request via the EPP command ‘domain:check’ from the EPP server must be carried out by the accredited registrars.

Related FAQs

My registrar is accredited for .lu; how can I check whether a domain name is available?

To find out if a domain name is available, including domains in quarantine or those pending creation, use the EPP command ‘domain:check’ from the EPP server.

  • If the domain name is not available, the reason why it isn't is stated.
  • If the domain name is already registered, run the command ‘domain:info’ to learn both which registrar it is registered at, and which ‘TransferProhibited’ or ‘TradeProhibited’ restriction(s) apply.

You can also use the DAS, which operates on port 4343, but then you won't have access to the domain names in quarantine, or pending creation.