Tag: dns client

Flash Windows Vista / XP DNS Cache With ipconfig Command

ipconfig is a Windows XP / 2000 / 2003 / Vista command utility that displays all current TCP/IP network configuration values and refreshes Dynamic Host Configuration Protocol DHCP and Domain Name System DNS settings. You can use the same tool to clear out Windows DNS cache. This command has /flushdns switch to flush and reset the contents of the DNS client resolver cache. During DNS troubleshooting, you can use this procedure to discard negative cache entries from the cache, as well as any other entries that have been added dynamically.

Command to Flush DNS Vista

Login as administrator

Just open command prompt ( Start > Run > and type cmd > Press [Enter] key)

Type the following command to flush the DNS resolver cache when troubleshooting DNS name resolution problems, type:

ipconfig /flushdns

As usual you read help by typing the following command:

ipconfig /?

Please see ipconfig command help page for more information.

/etc/resolve.conf or resolv.conf File Example

The resolv.conf file is the resolver configuration file. It is use to configure client side access to the Internet Domain Name System (DNS). This file defines which name servers to use.

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

Note: File name is /etc/resolv.conf and not /etc/resolve.conf.

Sample resolv.conf file

Following is an example of resolv.conf file:

search cyberciti.biz
nameserver 202.54.1.10
nameserver 202.54.1.11

Where,

  • search domain.com: The search list is normally determined from the local domain name; by default, it contains only the local domain name. So when you type nslookup www, it will be matched to www.cyberciti.biz
  • nameserver Name-server-IP-address: Point out to your your own nameserver or to ISP’s name server. Up to 3 name servers may be listed.

But how do I edit the /etc/resolv.conf file?

Use text editor such as vi or gedit from Linux desktop:
# vi /etc/resolv.conf

Default /etc/resolv.conf file

Following file should be work with any ISP in the world :)
# cat /etc/resolv.conf
Output:

nameserver 208.67.220.220
nameserver 208.67.222.222

For more information see How to Setup Linux as DNS client.