Occasionally your domain name server may need to be changed. It will be seen that it has not changed. So you have to flush the DNS. You can flash the local DNS server. But you can not flash the public DNS.

However, you will need to get help from Google to flush public DNS.

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Step #01: Goto Flush Cache Public DNS web console.

The type your domain name and select RR type like as A record. Fill out google reCAPTCHA “I’m not a robot” 

Step #02: Click Flush Cache button and wait for few minutes.

Now wait and see your domain name changed name server ip address.

Step #03: How to flush local dns server cache for windows 7/8.1/10

Open cmd with administrator privilege click Yes.

C:\WINDOWS\system32>ipconfig /flushdns
Windows IP Configuration
Successfully flushed the DNS Resolver Cache.
C:\WINDOWS\system32>

Now registerdns command

C:\WINDOWS\system32>ipconfig /registerdns
Windows IP Configuration

Renew command below

C:\WINDOWS\system32>ipconfig /renew

Windows IP Configuration

Ethernet adapter Ethernet:

Connection-specific DNS Suffix . : 01716XXXXXX
IPv4 Address. . . . . . . . . . . : 192.168.1.5
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1

Your name server can’t properly work then face many problem like as, can’t access local any host name on your network.

So be careful DNS server must be active all time and client resolve any host name.

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