Dependencies
============
Knot DNS has several dependencies:
* libtool
* autoconf > 2.65
* flex >= 2.5.31
* bison >= 2.3
* libssl >= 0.9.8
* liburcu >= 0.5.4

Optional packages:
* libcap-ng >= 0.6.4 for POSIX 1003.1e capabilites(7)
* ragel

Dependencies for building documentation:
* texinfo

Knot DNS requires compiler to support atomic intrinsics.
GCC version at least 4.1 supports legacy atomic builtins, however 4.7 or newer is preferred.
Clang supports atomics since version 2.9.

Installation
============

Knot DNS may be already included in your operating system distribution and
therefore can be installed from packages (Linux) or ports (BSD). This is
always preferred unless you want to test the latest features, contribute to
Knot development, or you just know what you are doing.

Following sections describe how to build Knot DNS from the source code.

Installation on Debian based distributions
==========================================

The following steps should work (verified in VirtualBox only)
on the distribution/architecture/release combinations as listed bellow.

----------------------------------------------
Debian         (AMD64, I386) 6.0.2.1 (squeeze)
Ubuntu Server  (AMD64, I386) 10.04 LTS
Ubuntu Desktop (AMD64, I386) 10.04 LTS
----------------------------------------------

# Make the system up-to-date
$ sudo apt-get update
$ sudo apt-get upgrade

# Ensure all prerequisites are installed
$ sudo apt-get install git-core autoconf libtool flex bison libssl-dev liburcu-dev

# Install optional packages (POSIX 1003.1e capabilities)
$ sudo apt-get install libcap-ng-dev

# If the liburcu-dev package is not present, install directly
$ wget http://bd.archive.ubuntu.com/ubuntu/pool/universe/libu/liburcu/liburcu0_0.5.4-1_amd64.deb
$ wget http://bd.archive.ubuntu.com/ubuntu/pool/universe/libu/liburcu/liburcu-dev_0.5.4-1_amd64.deb
$ sudo dpkg -i liburcu0_0.5.4-1_amd64.deb
$ sudo dpkg -i liburcu-dev_0.5.4-1_amd64.deb

# Go for the real thing
$ git clone git://git.nic.cz/knot-dns.git
$ cd knot
$ autoreconf -if
$ ./configure
$ make
$ sudo make install
$ sudo ldconfig

Alternative packages for I386:
$ # the required version of liburcu is not available in the default package
$ # sources.
$
$ wget http://bd.archive.ubuntu.com/ubuntu/pool/universe/libu/liburcu/liburcu0_0.5.4-1_i386.deb
$ wget http://bd.archive.ubuntu.com/ubuntu/pool/universe/libu/liburcu/liburcu-dev_0.5.4-1_i386.deb
$ sudo dpkg -i liburcu0_0.5.4-1_i386.deb
$ sudo dpkg -i liburcu-dev_0.5.4-1_i386.deb


Installation on Fedora
======================

Notice: Knot DNS is available in official distribution repositories since
Fedora 18 (Spherical Cow). Search for 'knot' package.

All commands with the '#' prompt should be run as the root user, commands with
the '$' prompt should be run as a regular non-root user.

Update the system:
# yum upgrade

Ensure all base development tools are available:
# yum install @buildsys-build

Ensure all prerequisites are installed:
# yum install libtool autoconf flex bison openssl-devel userspace-rcu-devel

You can also install optional packages:
# yum install libcap-ng-devel ragel

Download the latest source code from Git and compile it:
$ git clone git://git.nic.cz/knot-dns.git
$ cd knot
$ autoreconf -if
$ ./configure
$ make

Install Knot DNS into system (run only if you really know what these commands do):
# make install
# ldconfig

Installation on BSD
===================

Not all prerequisites are available as ports on BSD.

- liburcu must be compiled from sources
  - version 0.6.4 compiles on BSD without any source code modifications
  - in case of x86_64 build, CFLAGS nad build type has to be set appropriately.
    $ CFLAGS=-fPIC ./configure --build amd64
- flex must be newer version from ports that support reentrant parsers

Knot DNS requires more recent version of flex from ports, to prevent name clash
specify flex destination.
$ cd <knot sources>
$ autoreconf -if
$ ./configure
$ make && sudo make install

It is also present in port tree, so you can install it from there.
$ cd /usr/ports/dns/knot
$ sudo make install

Installation on OpenBSD/NetBSD
==============================
Also works for OS X, if you don't want to install gcc from ports.
Prerequisites:
- liburcu needs patch for absent compiler TLS capability
  - patch is located in "scripts/urcu-tls-compat.patch"
- patch compatible with liburcu-0.6.7
- liburcu >= 0.7.0 works out of the box
- flex and bison from packages

$ mkdir liburcu && cd liburcu
$ wget "http://lttng.org/files/urcu/userspace-rcu-0.6.7.tar.bz2"
$ patch -p1 < ../scripts/urcu-tls-compat.patch
$ autoconf && ./configure && make && sudo make install
$ # or follow installation instructions in INSTALL

Knot DNS installation is the same as in previous section (Installation on BSD).

Installation on OS X
====================

Not all prerequisites are preinstalled for OS X.

- liburcu must be compiled from sources
  - liburcu requires gcc-4.6 from MacPorts, as it depends on __thread keyword
  $ CC=gcc-mp-4.6 ARCH=x86_64 ./configure
  $ make && sudo make install
- liburcu >= 0.7.0 works with supplied compiler, however ARCH must still be set
  - alternative is to set it with configure parameter --target

Compiling Knot DNS with gcc-mp-4.6 is recommended, but not necessary.

Running
=======

First, each server needs configuration file.
Please see samples/knot.sample.conf for reference.
Minimal configuration can be found in samples/knot.min.conf
Configuration zone has to specify:
* storage for PID files, compiled zones etc.
* network interfaces
* served zones

$ cp samples/knot.min.conf myserver.conf
$ vim myserver.conf # or your favourite text editor
$ knotc -h # see what it can do

Prepare working directory.

$ mkdir -p /tmp/knot-minimal/samples; cp samples/example.com.zone /tmp/knot-minimal/samples/

Third, lets load server. You can do this by running 'knotd' directly, or with
'knotc' as well. Server is able to run in daemonized or interactive mode.
Lets start our server in interactive mode (parameter '-i') to see if it runs.

$ knotc -c myserver.conf -i start # start server in interactive mode

Running as daemon
=================

Controller runs server in daemonized mode as default. Disadvantage is, that
it closes stdout/stderr so you need to set up either syslog or logging to
own files in the configuration. Controller parameter '-w' waits for the
operation to finish. Let's test server functionality.

$ knotc -c myserver.conf -w start # start server
$ dig @$ADDR -p $PORT example.com # issue a query and see result
$ ...
$ knotc -c myserver.conf -w stop  # stop server