Create server cookies for clients that send client cookies. Needs to be turned on in the config file with: answer-cookie: yes A cookie-secret can be configured for anycast setups. Also adds an access control list that will allow queries with either a valid cookie or over a stateful transport.
Unbound
Unbound is a validating, recursive, caching DNS resolver. It is designed to be fast and lean and incorporates modern features based on open standards. If you have any feedback, we would love to hear from you. Don’t hesitate to create an issue on Github or post a message on the Unbound mailing list. You can learn more about Unbound by reading our documentation.
Compiling
Make sure you have the C toolchain, OpenSSL and its include files, and libexpat installed. Unbound can be compiled and installed using:
./configure && make && make install
You can use libevent if you want. libevent is useful when using many (10000) outgoing ports. By default max 256 ports are opened at the same time and the builtin alternative is equally capable and a little faster.
Use the --with-libevent=dir configure option to compile Unbound with libevent
support.
Unbound configuration
All of Unbound's configuration options are described in the man pages, which will be installed and are available on the Unbound documentation page.
An example configuration file is located in doc/example.conf.