In short DNS resolver is a server that converts domain names into IP addresses. Without it, your website would not be accessible. Here at Hostinger, we provide our own recommended DNS resolvers for your VPS by default.

In case you wish to use your own DNS resolvers (not recommended) you can do that by navigating to the VPS section, choosing the server to which you want to apply changes to:

Then opening the Settings page:

And selecting Change DNS resolvers:

This feature works by automatically updating your /etc/resolv.conf file on your VPS. So editing this file manually is not needed when specifying new DNS resolvers.