nslookup (from ''name server lookup'') is a

network administration Network management is the process of administering and managing computer networks. Services provided by this discipline include fault analysis, performance management, provisioning of networks and maintaining quality of service. Network managemen ...

command-line A command-line interpreter or command-line processor uses a command-line interface (CLI) to receive commands from a user in the form of lines of text. This provides a means of setting parameters for the environment, invoking executables and pro ...

tool for querying the

Domain Name System The Domain Name System (DNS) is a hierarchical and distributed naming system for computers, services, and other resources in the Internet or other Internet Protocol (IP) networks. It associates various information with domain names assigned to ...

(DNS) to obtain the mapping between

domain name A domain name is a string that identifies a realm of administrative autonomy, authority or control within the Internet. Domain names are often used to identify services provided through the Internet, such as websites, email services and more. As ...

and

IP address An Internet Protocol address (IP address) is a numerical label such as that is connected to a computer network that uses the Internet Protocol for communication.. Updated by . An IP address serves two main functions: network interface ident ...

, or other

DNS record The Domain Name System (DNS) is a hierarchical and distributed naming system for computers, services, and other resources in the Internet or other Internet Protocol (IP) networks. It associates various information with domain names assigned t ...

Overview

nslookup was a member of the

BIND BIND () is a suite of software for interacting with the Domain Name System (DNS). Its most prominent component, named (pronounced ''name-dee'': , short for ''name daemon''), performs both of the main DNS server roles, acting as an authoritative n ...

name server software. Early in the development of BIND 9, the

Internet Systems Consortium Internet Systems Consortium, Inc., also known as ISC, is a Delaware-registered, 501(c)(3) non-profit corporation that supports the infrastructure of the universal, self-organizing Internet by developing and maintaining core production-quality so ...

planned to deprecate nslookup in favor of

host A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County People *Jim Host (born 1937), American businessman * Michel Host ...

and

dig Digging, also referred to as excavation, is the process of using some implement such as claws, hands, manual tools or heavy equipment, to remove material from a solid surface, usually soil, sand or rock (geology), rock on the surface of Earth. Di ...

. This decision was reversed in 2004 with the release of BIND 9.3 and nslookup has been fully supported since then. Unlike

, nslookup does not use the operating system's local Domain Name System resolver library to perform its queries, and thus may behave differently. Additionally, vendor-provided versions may include output of other sources of name information, such as host files, and

Network Information Service The Network Information Service, or NIS (originally called Yellow Pages or YP), is a client–server directory service protocol for distributing system configuration data such as user and host names between computers on a computer network. Sun ...

. Some behaviors of nslookup may be modified by the contents of

resolv.conf resolv.conf is the name of a computer file used in various operating systems to configure the system's Domain Name System (DNS) resolver. The file is a plain-text file usually created by the network administrator or by applications that manage ...

. The

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which ...

version of nslookup was written by Andrew Cherenson. The

ReactOS ReactOS is a free and open-source operating system for amd64/i686 personal computers intended to be binary-compatible with computer programs and device drivers made for Windows Server 2003 and later versions of Windows. ReactOS has been noted a ...

version was developed by Lucas Suggs and is licensed under the

GPL The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general u ...

Usage

nslookup operates in interactive or non-interactive mode. When used interactively by invoking it without arguments or when the first argument is - (minus sign) and the second argument is a

hostname In computer networking, a hostname (archaically nodename) is a label that is assigned to a device connected to a computer network and that is used to identify the device in various forms of electronic communication, such as the World Wide Web. Hos ...

or Internet address of a name server, the user issues parameter configurations or requests when presented with the nslookup prompt (>). When no arguments are given, then the command queries the default server. The - (minus sign) invokes subcommands which are specified on the command line and should precede nslookup commands. In non-interactive mode, i.e. when the first argument is a name or Internet address of the host being searched, parameters and the query are specified as command line arguments in the invocation of the program. The non interactive mode searches the information for a specified host using the default name server.

References

External links

* Microsoft Windows *
nslookup
–

Microsoft TechNet Microsoft TechNet was a Microsoft web portal and web service for IT professionals. It included a library containing documentation and technical resources for Microsoft products, a learning center which provides online training, discussion forums ...

library *
Using NSlookup.exe

Microsoft Knowledge Base Microsoft Knowledge Base was (as of 2020, almost all articles now produce the message : Sorry, page not found) a repository of over 150,000 articles made available to the public by Microsoft Corporation. It contains information on many problems enco ...

* Unix-like OSs ** *
nslookup source code in ISC Gitlab repository (Mozilla Public License)
{{Windows commands DNS software Internet Protocol based network software OS/2 commands Unix network-related software Windows communication and services Windows administration

Overview

Usage

See also

References

Further reading

External links