So how do you set DNS namserver under Sun Solaris UNIX system? The resolver is a set of routines in the C library that provide access to the Internet Domain Name System (DNS). The resolver configuration file contains information that is read by the resolver routines the first time they are invoked by a process. The file is designed to be human readable and contains a list of keywords with values that provide various types of resolver information.
Internet address (in dot notation) of a name server that the resolver should query. Up to MAXNS (currently 3, see ) name servers may be listed, one per keyword. If there are multiple servers, the resolver library queries them in the order listed. To configure Solaris nameserver edit or modify /etc/resolv.conf file.
DNS Client Setup
First Create the file called /etc/resolv.conf – which includes the primary and secondary DNS server IP address for Solaris system, it can be your own DNS server or your ISPs DNS server:
# touch /etc/resolv.conf
Open /etc/resolv.conf using vi text editor:
# vi /etc/resolv.conf
Add the following lines to it:
- nameserver IP : It is IP of first DNS server
- search nixcraft.in : Default domain name to search. For example, if you type command nslookup www, it will search it as www.nixcraft.in
2) Enable the name resolving using DNS as follows:
# cp /etc/nsswitch.dns /etc/nsswitch.conf
3) Test new name server by running the nslookup command as follows:
# nslookup nixcraft.in
# /usr/sfw/sbin/nslookup nixcraft.in
Many new Linux user finds it difficult to setup / modify new name server address (NS1 / NS2).
Local name resolution is done via /etc/hosts file. If you have small network, use /etc/hosts file. DNS (domain name service is accountable for associating domain names with ip address, for example domain yahoo.com is easy to remember than IP address 22.214.171.124) provides better name resolution. To configure Linux as DNS client you need to edit or modify /etc/resolv.conf file. This file defines which name servers to use. You want to setup Linux to browse net or run network services like www or smtp; then you need to point out to correct ISP DNS servers:
In Linux and Unix like computer operating systems, the /etc/resolv.conf configuration file contains information that allows a computer connected to the Internet to convert alpha-numeric names into the numeric IP addresses that are required for access to external network resources on the Internet. The process of converting domain names to IP addresses is called “resolving.”
The resolv.conf file typically contains the IP addresses of nameservers (DNS name resolvers) that attempt to translate names into addresses for any node available on the network.
Setup DNS Name resolution
Steps to configure Linux as DNS client, first login as a root user (use su command):
Step # 1: Open /etc/resolv.conf file:
# vi /etc/resolv.conf
Step #2: Add your ISP nameserver as follows:
Note Max. three nameserver can be used/defined at a time.
Step # 3:Test setup nslookup or dig command:
$ dig www.nixcraft.com
$ nslookup www.nixcraft.com