The whois command searches for an object in a RFC 3912 database. Red Hat/CentOS/RHEL/Fedora Linux comes with client for the whois directory service called whois or jwhois. The jwhois is a whois client that accepts both traditional and finger-style queries under RHEL. You can install the same using the yum command.
Redhat / CentOS Install whois client command
Login as root and type the following yum command to install the jwhois client:
# yum install jwhois
# yum install whois
Loaded plugins: priorities, rhnplugin 70 packages excluded due to repository priority protections Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package jwhois.x86_64 0:4.0-18.el6 set to be updated --> Finished Dependency Resolution Dependencies Resolved ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: jwhois x86_64 4.0-18.el6 rhel-x86_64-server-6 104 k Transaction Summary ================================================================================ Install 1 Package(s) Upgrade 0 Package(s) Total download size: 104 k Installed size: 0 Downloading Packages: jwhois-4.0-18.el6.x86_64.rpm | 104 kB 00:00 Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Installing : jwhois-4.0-18.el6.x86_64 1/1 Installed: jwhois.x86_64 0:4.0-18.el6 Complete!
How do I use whois command?
The syntax is:
whois [options] public-ip-address
This version of the whois client tries to guess the right server to ask for the specified object. If no guess can be made it will connect to whois.networksolutions.com for NIC handles or whois.arin.net for IPv4 addresses and network names. You can use the whois command as follows:
$ whois cyberciti.biz
$ whois 126.96.36.199
[Querying whois.arin.net] [Redirected to rwhois.softlayer.com:4321] [Querying rwhois.softlayer.com] [rwhois.softlayer.com] %rwhois V-1.5:003fff:00 rwhois.softlayer.com (by Network Solutions, Inc. V-188.8.131.52) network:Class-Name:network network:ID:NETBLK-SOFTLAYER.184.108.40.206/19 network:Auth-Area:220.127.116.11/19 network:Network-Name:SOFTLAYER-18.104.22.168 network:IP-Network:22.214.171.124/29 network:IP-Network-Block:126.96.36.199-188.8.131.52 network:Organization;I:SoftLayer Technologies, Inc. network:Street-Address:1950 Stemmons Freeway Suite 2043 network:City:Dallas network:State:TX network:Postal-Code:75207 network:Country-Code:US network:Tech-Contact;I:email@example.com network:Abuse-Contact;I:firstname.lastname@example.org network:Admin-Contact;I:IPADM258-ARIN network:Created:20070218 network:Updated:20091220 network:Updated-By:email@example.com %referral rwhois://root.rwhois.net:4321/auth-area=. %ok
Lookup for domain names
Getting help about whois command
Type the following command:
$ man whois
$ whois --help
Usage: whois [OPTION]... OBJECT... -h HOST, --host HOST connect to server HOST -p PORT, --port PORT connect to PORT -H hide legal disclaimers --verbose explain what is being done --help display this help and exit --version output version information and exit These flags are supported by whois.ripe.net and some RIPE-like servers: -l find the one level less specific match -L find all levels less specific matches -m find all one level more specific matches -M find all levels of more specific matches -c find the smallest match containing a mnt-irt attribute -x exact match -b return brief IP address ranges with abuse contact -B turn off object filtering (show email addresses) -G turn off grouping of associated objects -d return DNS reverse delegation objects too -i ATTR[,ATTR]... do an inverse look-up for specified ATTRibutes -T TYPE[,TYPE]... only look for objects of TYPE -K only primary keys are returned -r turn off recursive look-ups for contact information -R force to show local copy of the domain object even if it contains referral -a also search all the mirrored databases -s SOURCE[,SOURCE]... search the database mirrored from SOURCE -g SOURCE:FIRST-LAST find updates from SOURCE from serial FIRST to LAST -t TYPE request template for object of TYPE -v TYPE request verbose template for object of TYPE -q [version|sources|types] query specified server info
WHOIS is a query and response protocol used for querying databases that store the registered users or assignees of an Internet resource, such as a domain name, an IP address block. This page explained how to install whois client on Redhat (RHEL)/CentOS using yum command. See whois server list for top level domains here.