# 3. Installation¶

## 3.1. Packages¶

Starting with Kea 1.6.0, ISC now publishes native RPM, deb and APK packages along with the tarballs with the source code. The packages are available on Cloudsmith at https://cloudsmith.io/~isc/repos. You can download the native packages and install them using the system available in your distribution (such as dpkg or rpm). Also, you can add the Kea repository to your system, which will make it easier to install updates. For details, please go to https://cloudsmith.io/~isc/repos, choose the repository of interest and then click the Set Me Up button for detailed instructions.

## 3.2. Installation Hierarchy¶

The following is the directory layout of the complete Kea installation. (All directory paths are relative to the installation directory):

• etc/kea/ — configuration files.
• include/ — C++ development header files.
• lib/ — libraries.
• lib/kea/hooks — additional hooks libraries.
• sbin/ — server software and commands used by the system administrator.
• share/kea/ — configuration specifications and examples.
• share/doc/kea/ — this guide, other supplementary documentation, and examples.
• share/man/ — manual pages (online documentation).
• var/lib/kea/ — server identification, and lease databases files.
• var/log/ - log files.
• var/run/kea - pid and logger lock files.

## 3.3. Build Requirements¶

In addition to the run-time requirements (listed in Required Software at Run-Time), building Kea from source code requires various development include headers and program development tools.

Note

Some operating systems have split their distribution packages into a run-time and a development package. You will need to install the development package versions, which include header files and libraries, to build Kea from the source code.

Building from source code requires the following software installed on the system:

• Boost C++ libraries (https://www.boost.org/). The oldest Boost version used for testing is 1.57 (although it may also work with older versions). The Boost system library must also be installed. Installing a header-only version of Boost is no longer recommended.
• OpenSSL (at least version 1.0.1) or Botan (at least version 2). Note that OpenSSL version 1.0.2 or 1.1.0 or later is strongly recommended.
• log4cplus (at least version 1.0.3) development include headers.
• A C++ compiler (with C++11 support) and standard development headers. The Kea build has been checked with GCC g++ 4.8.5 and some later versions, and Clang 800.0.38 and some later versions.
• The development tools automake, libtool, and pkg-config.
• The MySQL client and the client development libraries, when using the –with-mysql configuration flag to build the Kea MySQL database backend. In this case, an instance of the MySQL server running locally or on a machine reachable over a network is required. Note that running the unit tests requires a local MySQL server.
• The PostgreSQL client and the client development libraries, when using the –with-pgsql configuration flag to build the Kea PostgreSQL database backend. In this case an instance of the PostgreSQL server running locally or on some other machine, reachable over the network from the machine running Kea, is required. Note that running the unit tests requires a local PostgreSQL server.
• The cpp-driver from DataStax is needed when using the –with-cql configuration flag to build Kea with the Cassandra database backend. In this case, an instance of the Cassandra server running locally or on some other machine, reachable over the network from the machine running Kea, is required. Note that running the unit tests requires a local Cassandra server.
• The FreeRADIUS client library is required to connect to a RADIUS server. (This is specified using the –with-freeradius configuration switch.)
• Sysrepo (version 0.7.6 or later) and libyang (version 0.16-r2 or later) are needed to connect to a Sysrepo database. (This is specified using the –with-sysrepo switch when running “configure”.)
• googletest (version 1.8 or later) is required when using the –with-gtest configuration option to build the unit tests.
• The documentation generation tools Sphinx, texlive with its extensions and Doxygen, if using the –enable-generate-docs configuration option to create the documentation. Particularly, in case of Fedora: python3-sphinx, texlive and texlive-collection-latexextra; in case of Ubuntu: python3-sphinx, python3-sphinx-rtd-theme and texlive-binaries. If LaTeX packages are missing, Kea will skip PDF generation and will produce only HTML documents.

Visit ISC’s Knowledgebase at https://kb.isc.org/docs/installing-kea for system-specific installation tips.

## 3.4. Installation from Source¶

Although Kea may be available in pre-compiled, ready-to-use packages from operating system vendors, it is open source software written in C++. As such, it is freely available in source code form from ISC as a downloadable tar file. The source code can also be obtained from the Kea Gitlab repository at https://gitlab.isc.org/isc-projects/kea. This section describes how to build Kea from the source code.

### 3.4.2. Retrieve from Git¶

Downloading this “bleeding edge” code is recommended only for developers or advanced users. Using development code in a production environment is not recommended.

Note

When building from source code retrieved via git, additional software will be required: automake (v1.11 or later), libtoolize, and autoconf (v2.69 or later). These may need to be installed.

The latest development code is available on GitLab (see https://gitlab.isc.org/isc-projects/kea). The Kea source is public and development is done in the “master” branch.

The code can be checked out from https://gitlab.isc.org/isc-projects/kea.git:

$git clone https://gitlab.isc.org/isc-projects/kea.git  The code checked out from the git repository does not include the generated configure script, the Makefile.in files, nor their related build files. They can be created by running autoreconf with the --install switch. This will run autoconf, aclocal, libtoolize, autoheader, automake, and related commands. Write access to the Kea repository is only granted to ISC staff. If you are a developer planning to contribute to Kea, please check our Contributor’s Guide. The Kea Developer’s Guide contains more information about the process, as well as describes the requirements for contributed code to be accepted by ISC. ### 3.4.3. Configure Before the Build¶ Kea uses the GNU Build System to discover build environment details. To generate the makefiles using the defaults, simply run: $ ./configure


Run ./configure with the --help switch to view the different options. Some commonly used options are:

• --prefix Define the installation location (the default is /usr/local).
• --with-mysql Build Kea with code to allow it to store leases and host reservations in a MySQL database.
• --with-pgsql Build Kea with code to allow it to store leases and host reservations in a PostgreSQL database.
• --with-cql Build Kea with code to allow it to store leases and host reservations in a Cassandra (CQL) database.
• --with-log4cplus Define the path to find the Log4cplus headers and libraries. Normally this is not necessary.
• --with-boost-include Define the path to find the Boost headers. Normally this is not necessary.
• --with-botan-config Specify the path to the botan-config script to build with Botan for cryptographic functions. It is preferable to use OpenSSL (see below).
• --with-openssl Replace Botan by the OpenSSL the cryptographic library. By default configure searches for a valid Botan installation. If one is not found, it searches for OpenSSL. Normally this is not necessary.
• --enable-shell Build the optional kea-shell tool (more in The Kea Shell). The default is to not build it.
• --with-site-packages Only useful when kea-shell is enabled. It causes the kea-shell python packages to be installed in specified directory. This is mostly useful for Debian related distros. While most systems store python packages in ${prefix}/usr/lib/pythonX/site-packages, Debian introduced separate directory for packages installed from DEB. Such python packages are expected to be installed in /usr/lib/python3/dist-packages. • --enable-perfdhcp Build the optional perfdhcp DHCP benchmarking tool. The default is to not build it. • --with-freeradius Build the optional RADIUS hook. This option specifies path to the patched version of FreeRADIUS client. Available in subscriber only version. This option requires subscription-only RADIUS hook. • --with-freeradius-dictionary Specifies a non-standard location for a FreeRADIUS dictionary file. That file contains list of supported RADIUS attributes. Available in subscriber only version. This option requires subscription-only RADIUS hook. If you don’t see the RADIUS options, make sure you have RADIUS hook sources in the premium directory and rerun autoreconf -i. Note The --runstatedir in the installation directories is particular. There are three cases: • You use autoconf 2.70 or greater which supports this, but this autoconf version has not been released yet. • You use autoconf 2.69 patched to add support of this. In this case and the previous simply use when needed the–runstatedir configure parameter. • There is no support (the configure parameter is not recognized and configure directly raises an error). For autoconf 2.69 the runstatedir environment variable is supported so simply remove the -- before runstatedir in the configure script call, e.g.: ./configure runstatedir=/opt/run ... Note For instructions concerning the installation and configuration of database backends for Kea, see DHCP Database Installation and Configuration. There are also many additional options that are typically not necessary for regular users. However, they may be useful for package maintainers, developers, or people who want to extend Kea code or send patches: • --with-gtest, --with-gtest-source Enable the building of the C++ Unit Tests using the Google Test framework. This option specifies the path to the gtest source. (If the framework is not installed on your system, it can be downloaded from https://github.com/google/googletest.) • --enable-generate-docs Enable the rebuilding Kea documentation. ISC publishes Kea documentation for each release; however, in some cases you may want to rebuild it. For example, if you want to change something in the docs, or want to generate new ones from git sources that are not released yet. • --enable-generate-parser Many Kea components have parsers implemented using flex (.ll files) and bison (.yy files). Kea sources have C++/h files generated out from them. By default Kea does not use flex or bison to avoid requiring installation of unnecessary dependencies for users. However, if you change anything in the parses (such as adding a new parameter), you will need to use flex and bison to regenerate parsers. This option lets you do that. • --enable-generate-messages Enable the regeneration of messages files from their messages source files, e.g. regenerate xxx_messages.h and xxx_messages.cc from xxx_messages.mes using the Kea message compiler. By default Kea is built using these .h and .cc files from the distribution. However, if you change anything in a .mes file (such as adding a new message), you will need to build and use the Kea message compiler. This option lets you do that. • --with-benchmark, --with-benchmark-source Enable the building of the database backend benchmarks using the Google Benchmark framework. This option specifies the path to the gtest source. (If the framework is not installed on your system, it can be downloaded from https://github.com/google/benchmark.) This support is experimental. For example, the following command configures Kea to find the Boost headers in /usr/pkg/include, specifies that PostgreSQL support should be enabled, and sets the installation location to /opt/kea: $ ./configure \
--with-boost-include=/usr/pkg/include \
--with-pgsql=/usr/local/bin/pg_config \
--prefix=/opt/kea


If you have any problems with building Kea using the header-only Boost code, or you’d like to use the Boost system library (assumed for the sake of this example to be located in /usr/pkg/lib):



### 3.4.5. Install¶

To install the Kea executables, support files, and documentation, issue the command:

$make install  Do not use any form of parallel or job server options (such as GNU make’s -j option) when performing this step; doing so may cause errors. Note The install step may require superuser privileges. If required, run ldconfig as root with /usr/local/lib (or with prefix/lib if configured with –prefix) in /etc/ld.so.conf (or the relevant linker cache configuration file for your OS): $ ldconfig


Note

If you do not run ldconfig where it is required, you may see errors like the following:

program: error while loading shared libraries: libkea-something.so.1:
cannot open shared object file: No such file or directory


### 3.4.6. Cross-Building¶

It is possible to cross-build Kea, i.e. to create binaries in another system (the build system) than the system where Kea will run (the host system).

It is outside of the scope of common administrator operations and requires some developer skills so the Developer Guide explains how to do that using a x86_64 Linux system to build Kea for a Raspberry Pi box running Raspbian: Kea Cross-Compiling Example.

## 3.5. DHCP Database Installation and Configuration¶

Kea stores its leases in a lease database. The software has been written in a way that makes it possible to choose which database product should be used to store the lease information. Kea supports four database backends: MySQL, PostgreSQL, Cassandra, and memfile. To limit external dependencies, MySQL, PostgreSQL, and Cassandra support are disabled by default and only memfile is available. Support for the optional external database backend must be explicitly included when Kea is built. This section covers the building of Kea with one of the optional backends and the creation of the lease database.

Note

When unit tests are built with Kea (i.e. the –with-gtest configuration option is specified), the databases must be manually pre-configured for the unit tests to run. The details of this configuration can be found in the Kea Developer’s Guide.

### 3.5.1. Building with MySQL Support¶

Install MySQL according to the instructions for your system. The client development libraries must be installed.

Build and install Kea as described in Installation, with the following modification. To enable the MySQL database code, at the “configure” step (see Configure Before the Build), the –with-mysql switch should be specified:

$./configure [other-options] --with-mysql  If MySQL was not installed in the default location, the location of the MySQL configuration program “mysql_config” should be included with the switch, i.e. $ ./configure [other-options] --with-mysql=path-to-mysql_config


See First-Time Creation of the MySQL Database for details regarding MySQL database configuration.

### 3.5.2. Building with PostgreSQL support¶

Install PostgreSQL according to the instructions for your system. The client development libraries must be installed. Client development libraries are often packaged as “libpq”.

Build and install Kea as described in Installation, with the following modification. To enable the PostgreSQL database code, at the “configure” step (see Configure Before the Build), the –with-pgsql switch should be specified:

$./configure [other-options] --with-pgsql  If PostgreSQL was not installed in the default location, the location of the PostgreSQL configuration program “pg_config” should be included with the switch, i.e. $ ./configure [other-options] --with-pgsql=path-to-pg_config


See First-Time Creation of the PostgreSQL Database for details regarding PostgreSQL database configuration.

### 3.5.3. Building with CQL (Cassandra) Support¶

Install Cassandra according to the instructions for your system. The Cassandra project website contains useful pointers: https://cassandra.apache.org.

If you have a cpp-driver package available as binary or as source, simply install or build and install the package. Then build and install Kea as described in Installation. To enable the Cassandra (CQL) database code, at the “configure” step (see Configure Before the Build), enter:

$./configure [other-options] --with-cql=path-to-pkg-config  Note if pkg-config is at its standard location (and thus in the shell path) you do not need to supply its path. If it does not work (e.g. no pkg-config, package not available in pkg-config with the cassandra name), you can still use the cql_config script in tools/ as described below. Download and compile cpp-driver from DataStax. For details regarding dependencies for building cpp-driver, see the project homepage https://github.com/datastax/cpp-driver. In June 2016, the following commands were used: $ git clone https://github.com/datastax/cpp-driver
$cd cpp-driver$ mkdir build
$cd build$ cmake ..
$make  As of January 2019, cpp-driver does not include cql_config script. Work is in progress to contribute such a script to the cpp-driver project but, until that is complete, intermediate steps need to be conducted. A cql_config script is present in the tools/ directory of the Kea sources. Before using it, please create a cql_config_defines.sh file in the same directory (there is an example available in cql_config_define.sh.sample; you may copy it over to cql_config_defines.sh and edit the path specified in it) and change the environment variable CPP_DRIVER_PATH to point to the directory where the cpp-driver sources are located. Make sure that appropriate access rights are set on this file. It should be executable by the system user building Kea. Build and install Kea as described in Installation, with the following modification. To enable the Cassandra (CQL) database code, at the “configure” step (see Configure Before the Build), enter: $ ./configure [other-options] --with-cql=path-to-cql_config


## 3.6. Hammer Building Tool¶

An optional building tool called Hammer was introduced with Kea 1.6.0. It is a Python 3 script that lets users automate tasks related to building Kea, such as setting up virtual machines, installing Kea dependencies, compiling Kea with various options, running unit-tests and more. This tool was created primarily for internal QA purposes at ISC and it is not included in the Kea distribution. However, it is available in the Kea git repository. This tool was developed primarily for internal purposes and ISC cannot guarantee its proper operation. If you decide to use it, please do so with care.

Note

Use of this tool is completely optional. Everything it does can be done manually.

The first-time user is strongly encouraged to look at Hammer’s built-in help:

$./hammer.py --help  It will list available parameters. Hammer is able to set up various operating systems running either in LXC or in VirtualBox. To list of supported systems, use the supported-systems command: $ ./hammer.py supported-systems
fedora:
- 27: lxc, virtualbox
- 28: lxc, virtualbox
- 29: lxc, virtualbox
centos:
- 7: lxc, virtualbox
rhel:
- 8: virtualbox
ubuntu:
- 16.04: lxc, virtualbox
- 18.04: lxc, virtualbox
- 18.10: lxc, virtualbox
debian:
- 8: lxc, virtualbox
- 9: lxc, virtualbox
freebsd:
- 11.2: virtualbox
- 12.0: virtualbox


It is also possible to run the build locally, in the current system (if the OS is supported).

First, you must install the Hammer dependencies: Vagrant and either VirtualBox or LXC. To make life easier, Hammer can install Vagrant and the required Vagrant plugins using the command:

$./hammer.py ensure-hammer-deps  VirtualBox and LXC need to be installed manually. The basic functions provided by Hammer are to prepare the build environment and perform the actual build, and to run the unit tests locally in the current system. This can be achieved by running the command: $ ./hammer.py build -p local


The scope of the process can be defined using –with (-w) and –without (-x) options. By default the build command will build Kea with documentation, install it locally, and run unit tests.

To exclude the installation and generation of docs, type:

$./hammer.py build -p local -x install docs  The basic scope can be extended by: mysql, pgsql, cql, native-pkg, radius, shell, and forge. Note To build Kea locally, Hammer dependencies like Vagrant are not needed. Hammer can be told to set up a new virtual machine with a specified operating system, without the build: $ ./hammer.py prepare-system -p virtualbox -s freebsd -r 12.0


This way we can prepare a system for our own use. To get to such a system using SSH, invoke:

$./hammer.py ssh -p virtualbox -s freebsd -r 12.0  It is possible to speed up subsequent Hammer builds. To achieve this Hammer employs ccache. During compilation, ccache stores objects in a shared folder. In subsequent runs, instead of doing an actual compilation, ccache returns the stored earlier objects. The cache with these objects for reuse needs to be stored outside of VM or LXC. To indicate the folder, you must indicate the –ccache-dir parameter for Hammer. In the indicated folder, there are separate stored objects for each target operating system. $ ./hammer.py build -p lxc -s ubuntu -r 18.04 --ccache-dir ~/kea-ccache


Note

ccache is currently only supported for LXC in Hammer; support for VirtualBox may be added later.

\$ ./hammer.py --help


## 3.7. Running Kea from non-root account on Linux¶

Both Kea DHCPv4 and DHCPv6 servers perform operations that in general require root access privileges. In particular, DHCPv4 opens raw sockets and both DHCPv4 and DHCPv6 open UDP sockets on privileged ports. However, with some extra system configuration, it is possible to run Kea from non-root accounts.

First, a regular user account must be created:

useradd admin


Then, change the binaries ownership and group to new user. Note your path may be different. Please refer to the --prefix parameter passed to the configure script.:

chown -R admin /opt/kea


Assuming you are using systemd, you also should modify its service file (e.g. /etc/systemd/system/kea-dhcp6.service):

User=admin


The most important step is to set capabilities of the binaries. Refer to man capabilities to get more information.

setcap 'cap_net_bind_service=+ep' /opt/kea/sbin/kea-dhcp4
setcap 'cap_net_raw=+ep' /opt/kea/sbin/kea-dhcp4
setcap 'cap_net_bind_service=+ep' /opt/kea/sbin/kea-dhcp6


After this step is complete, the admin user should be able to run Kea. Note that DHCPv4 server by default opens raw sockets. If your network is only using relayed traffic, you can instruct Kea to use regular UDP sockets (refer to dhcp-socket-type parameter in the Interface Configuration section) and the cap_net_raw capability can be skipped.

Note

An alternative approach to avoiding running Kea with root privileges assumes instructing Kea to use non-privileged (greater than 1024) posts and redirecting traffic. This, however, will work only for relayed traffic. This approach in general is considered experimental and not tested enough for deployment in production environment. Use with caution!

To use this approach, configure the server to listen on other non privileged port (eg: 1547 and 1548) by running the process with -p option in /etc/systemd/system/kea-dhcp4.service:

ExecStart=/opt/kea/sbin/kea-dhcp4 -d -c /etc/kea/kea-dhcp4.conf -p 2067


and /etc/systemd/system/kea-dhcp4.service:

ExecStart=/opt/kea/sbin/kea-dhcp6 -d -c /etc/kea/kea-dhcp6.conf -p 1547


and then configure port redirection with iptables and ip6tables for new ports (eg: 1547 and 1548). Make sure you replace ens4 with your specific interface name.

iptables -t nat -A PREROUTING -i ens4 -p udp --dport 67 -j REDIRECT --to-port 2067
iptables -t nat -A PREROUTING -i ens4 -p udp --dport 2068 -j REDIRECT --to-port 68
ip6tables -t nat -A PREROUTING -i ens4 -p udp --dport 547 -j REDIRECT --to-port 1547
ip6tables -t nat -A PREROUTING -i ens4 -p udp --dport 1548 -j REDIRECT --to-port 548