nslookup

Thenslookup command
Developer(s)	Andrew Cherenson,Internet Systems Consortium,IBM,Microsoft, Lucas Suggs
Operating system	Unix,Unix-like,OS/2,Microsoft Windows,ReactOS
Platform	Cross-platform
Type	Command
License	BSD

nslookup (fromname server lookup) is anetwork administrationcommand-line tool for querying theDomain Name System (DNS) to obtain the mapping betweendomain name andIP address, or otherDNS records.

nslookup is a member of theBIND name server software. Andrew Cherenson created nslookup as a class project at UC Berkeley in 1986 and it first shipped in 4.3-Tahoe BSD^[1]In the development of BIND 9, theInternet Systems Consortium planned to deprecate nslookup in favor ofhost anddig. This decision was reversed in 2004 with the release of BIND 9.3^[2] and nslookup has been fully supported since then.

Unlikedig, 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 the output of other sources of name information, such ashost files, andNetwork Information Service. Some behaviors of nslookup may be modified by the contents ofresolv.conf.^[3]

TheLinux version of nslookup is the original BSD version written by Andrew Cherenson.^[4]

TheReactOS version was developed by Lucas Suggs and is licensed under theGPL.^[5]

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 ahostname 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.^[6]

• dig, a utility that interrogates DNS servers directly for troubleshooting and system administration purposes.
• host is a simple utility for performing Domain Name System lookups.
• List of DNS record types - possible types of records stored and queried within DNS
• Root name server - top-level name servers providing top level domain name resolution
• whois
• BIND name server

• Barrett, Daniel J. (2012).Macintosh Terminal Pocket Guide: Take Command of Your Mac.O'Reilly.ISBN 978-1449328986.
• Stanek, William R. (2008).Windows Command-Line Administrator's Pocket Consultant, 2nd Edition.Microsoft Press.ISBN 978-0735622623.

Wikiversity has learning resources aboutNslookup

Wikibooks has a book on the topic of:Guide to Windows Commands

Microsoft Windows

• nslookup –Microsoft TechNet library
• Using NSlookup.exe,Microsoft Knowledge Base

Unix-like OSs

• nslookup(1) – Linux User CommandsManual
• 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

• Articles with short description
• Short description matches Wikidata