ISC Kea

Testbed for building ISC Kea software on Alpine Linux for OpenNebula's VNF appliance.

NOTE: Custom ONELease Hook for ISC Kea is under src/hooks.

IMPORTANT: I am archiving this repo and future updates will be in the official OpenNebula fork: https://github.com/OpenNebula/addon-kea-hooks

OpenNebula VNF

One of the VNFs for OpenNebula's VNF appliance is a dhcp and Kea with its custom hooks was the best solution for our requirement (matching HW address with the IP lease) - dnsmasq has some hook system too, but they are triggered too late (after the lease is actually done). Kea's hooks are more granular and hooked onto more places during the process, which scratches our itch.

Content overview

Here is a layout of this repository:

ikea/
├── artifacts/          # Ready to use builds
├── Dockerfile
├── extra/              # Some handy scripts
├── CHANGELOG.md
├── ikea.sh
├── LICENSE
├── Makefile
├── Makefile.config
├── README.md
├── src/
│   ├── hooks/          # Custom hooks
│   └── tools/          # Custom tools
└── tools/              # Build helpers

• artifacts: Here are already build and packed releases
• src: All custom work
• src/hooks: Custom Kea hooks
• src/tools: Custom Kea related scripts and tools
• The rest is build related

Usage

First of all you need installed docker and make command. This project (if successful) will create a few artifacts:

• docker image with build and installed ISC Kea (also saved as a tar)
• an archive with ISC Kea compiled binaries (installation prefix)

The archive is used as a artifact for ONE VNF appliance - rebuilding ISC Kea with each appliance build would be too time-consuming.

List default build parameters

There is no configure script so just edit or set the environmental variables which have defaults here:

% cat Makefile.config

Default build

% make
% ls -l build

OpenNebula build

For OpenNebula's ONE VNF appliance there exists a handy script (adjust MAKE_JOBS to your setup):

% ./extra/onekea.sh

For example with eight parallel jobs (instead of the default four):

% MAKE_JOBS=8 ./extra/onekea.sh

Or do something like this:

% env MAKE_JOBS=8 KEA_INSTALLPREFIX=/opt/one-appliance/kea make

Hooks

To build hook(s) in this repo and package it with the artifact you must use variable INSTALL_HOOKS - it will build and install only that hook which has corresponding KEA_VERSION. Check the default version in Makefile.config or set it on the command line:

% env MAKE_JOBS=8 INSTALL_HOOKS=yes KEA_VERSION=1.6.0 make

Hook's source code can be found under src/hooks directory: src/hooks/<hook>/<kea version>

Custom hook libraries (build binaries) are packaged with the rest of the Kea software and they can be found under: <KEA_INSTALLPREFIX>/lib/kea/hooks/

Even if all hooks are build, installed and packaged it does not mean that any of it will be loaded and used...what hook (library) is loaded and activated on Kea's startup is ultimately decided by your config file.

Tools

The directory src/tools is intended for helper tools and scripts directed to the ISC Kea runtime - that means they have nothing to do with the building of ikea as opposed to the tools directory under root of this repository...

• kea-config-generator: designed for OpenNebula's VNF appliance, but can be used elsewhere too

kea-config-generator

It creates a kea-dhcp4.conf config file based on the given arguments. When no arguments is given it will create a config based on some simple heuristics.

The intent behind this script is to support OpenNebula's VNF appliance, but it is generic enough to be used anywhere where Kea's config file is to be autogenerated.

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Issues

I decided to create this repo to build ISC Kea manually and use its artifacts in the appliance until Alpine kea packages are fixed and in stable branch...

log4cplus problem

Kea packages built for Alpine are only in Edge and very unstable. I encountered a problem when kea binaries have been used as (on Alpine):

# ./kea-dhcp4 -c /etc/kea/kea-dhcp4.conf
kea-dhcp4: Fatal error during start up: log4cplus is not initialized and implicit initialization is turned off

Bugreports already existed:

• https://gitlab.isc.org/isc-projects/kea/issues/625
• https://gitlab.alpinelinux.org/alpine/aports/issues/10480

Alpine kea packages dependency problem

Newest version of kea packages in Edge have for a change broken dependency last time I checked.