Install Unbound DNS caching server

Unbound is an Open source DNS caching and recursive resolver. You can find more about unbound at

To install unbound on Ubuntu/Debian, run

To start unbound

Set unbound to start on boot

To configure your server to use local name servers provided by unbound, edit file


See dns


Delegate a sub domain to DNS server

To point a domain to another server, you can create an A record, point to the server.

If your provider only provide name servers and no fixed IP, you can create NS record for your sub domain like

Here is how i added NS record in Amazon Route 53



dig is a command line tool like nslookup used to check dns,

Here is the basic usage

dig have multiple sections, ANSWER SECTION is what you need to look for. After answer section, it shows some info about DNS server used to query.


+short option allow you to just slow the answer.

To find Specific Record type



DNS Resolver

CloudFlare announced privacy-first consumer DNS service.

IP of CloudFlare public DNS servers are

So far i was using Google Public DNS servers as my resolver.


Quad9 is from IMB and Global Cyber Allience.

Other public DNS server is OpenDNS

All these DNS servers have good connectivity in india. I get ~65 ping to these serves, that is normal for indian servers.

On linux you can configure DNS server by editing file



DNS Resolver

DNS Tools

DNS Errors