# Kea 1.7.0, September 25th 2019, Release Notes Welcome to Kea 1.7.0, the first of a monthly development releases of Kea. This release is the first step towards having fully multi-threaded DHCP servers, which will eventually become available as 1.8.0. It contains first preliminary steps moving us closer to that goal. Changes introduced in this version: 1. **Preliminary multi-threading work**. The team spent much time doing experiments with multi-threaded POC (proof of concept), discussing the threading design (#874) and making first preliminary code changes. In particular, we now migrated to standard c++11 threads, rather than using our custom wrappers (#914). 2. **Statistics update**. There's a change in how Kea handles statistics. The previous approach was using lazy initialization pattern. Previously Kea started empty, without any statistics. The statistics became available when the first observation was recorded. This had a drawback of usually not reporting statistics that are unlikely to happen, such as receiving DECLINE message. Right now Kea reports statistics up front, without needing to wait for an actual event that triggers it to happen. (#755) 3. **No longer allocate memory in signal handler**. Kea no longer allocates memory while in signal handler. We received a report of possible problems when handling signals during command processing. Despite our best efforts, we were not able to reproduce the problem. However, based on the detailed bug report we were able to come up with a fix that hopefully addresses the problem. (#796) 4. **DHCPv4 sanity checks improved**. The DHCPv4 server now properly drops packets that don't have any client identification (no MAC address and no client-id). (#821) 5. **Fixed FreeRADIUS packages**. We discovered that our FreeRADIUS packages were built incorrectly. This is now fixed. (#909) 6. **Cassandra build improvements**. We improved the build routines for Cassandra. The previously broken capability to build Cassandra backend from cpp-sources that are not installed is now fixed (#522). ## Changes to Release Model Kea project has been in development for several years now. It now has a significant production deployment base with users who are looking for stability, rather than constant stream of new bleeding edge features. At the same time, we want to continue developing the software, including some new powerful, but difficult to implement features. As a result, we decided to change the release cycle. Starting from 1.6.0, there will be two series of releases: stable and development. Stable releases are what you would expect: stable, released infrequently, without new features or significant changes, very well tested. Those can be identified by the middle version number being even. The current stable is 1.6.0. If we discover important bugs that require fixing, we may release 1.6.1, but that will be determined on a case by case basis. The next major stable version will be 1.8.0 and some time later 2.0.0. Our team continues development of new features. In particular, we're tackling a difficult problem of being able to use all available CPU cores simultaneously. The multi-threading implementation is a complex task and it is uncertain how long it will take before the solution is stable and ready for production environment. At the same time, we continue to receive a stream of requests for small features and bug fixes. We don't want to force the users to wait half a year or more for the fixes and features that are already done. Therefore we decided to start releasing development releases on a monthly basis. Those are slightly less tested and may have features that are not complete. A good example may be multi-threading. It is possible that one of the next releases will provide a configuration knob to specify the number of threads, but the actual code won't be extended yet to spawn those threads. THe development releases can be easily identified by the middle version number being odd. For example, 1.7.0 is a development release. In October we will release 1.7.1, the next development version. Once 1.8.0 is out, we will continue our development work on 1.9.0, then 1.9.1 and so on. We're aiming at making the development release available on the last Wednesday of each month. There may be exceptions (such as Christmas 2019), but that's the general goal. We encourage users to test the development releases and report back their findings. For more details on the plan, see ISC's Software Support Policy at https://kb.isc.org/v1/docs/aa-00896. ## Kea overview Kea is a DHCP implementation developed by Internet Systems Consortium, Inc. that features fully functional DHCPv4 and DHCPv6 servers, a dynamic DNS update daemon, a Control Agent (CA) that provides a REST API to control the DHCP and DNS update servers, an example shell client to connect to the CA, a daemon that is able to retrieve YANG configuration and updates from Sysrepo, and a DHCP performance-measurement tool. Both DHCP servers fully support server discovery, address assignment, renewal, rebinding, release, decline, information request, DNS updates, client classification, and host reservations. The DHCPv6 server also supports prefix delegation. Lease information is stored in a CSV file by default; it can optionally be stored in a MySQL, PostgreSQL, or Cassandra database instead. Host reservations can be stored in a configuration file, or in a MySQL, PostgreSQL, or Cassandra database. They can also be retrieved from a RADIUS server, although this functionality is somewhat limited. Kea DHCPv4 and DHCPv6 daemons provide support for YANG models, which are stored in a Sysrepo datastore and can be configured via the NETCONF protocol. This text references issue numbers. For more details, visit the Kea GitLab page at https://gitlab.isc.org/isc-projects/kea/issues. ## License This version of Kea is released under the Mozilla Public License, version 2.0. https://www.mozilla.org/en-US/MPL/2.0 The premium and subscriber-only hook libraries are provided in source code form, under the terms of an End User License Agreement (you will get the source code that you can modify freely, but you are not permitted to redistribute it). ## Download Pre-built ISC packages for current versions of the most popular Linux operating systems are available at: https://cloudsmith.io/~isc/repos/ The Kea source and PGP signature for this release may be downloaded from: https://www.isc.org/downloads The signature was generated with the ISC code signing key which is available at: https://www.isc.org/pgpkeys ISC provides detailed documentation, including installation instructions and usage tutorials, in the Kea Administrator Reference Manual. Documentation is included with the installation or via https://kb.isc.org/docs/kea-administrator-reference-manual in HTML, plain text, or PDF formats. ISC maintains a public open source code tree, wiki, issue tracking system, milestone planning, and a roadmap at https://gitlab.isc.org//isc-projects/kea. Limitations and known issues with this release can be found at https://gitlab.isc.org/isc-projects/kea/wikis/known-issues-list. We ask users of this software to please let us know how it worked for you and what operating system you tested on. Feel free to share your feedback on the Kea Users mailing list (https://lists.isc.org/mailman/listinfo/kea-users). Also we would like to hear whether the documentation is adequate and accurate. Please open tickets in the Kea GitLab project for bugs, documentation omissions and errors, and enhancement requests. We want to hear from you even if everything worked. ## Support Professional support for Kea is available from ISC. We encourage all professional users to consider this option; Kea maintenance is funded with support subscriptions. For more information on ISC's Kea and DHCP software support see https://www.isc.org/support/. Free best-effort support is provided by our user community via a mailing list. Information on all public email lists is available at https://www.isc.org/community/mailing-list. If you have any comments or questions about working with Kea, please share them to the Kea Users List (https://lists.isc.org/mailman/listinfo/kea-users). Bugs and feature requests may be submitted via GitLab at https://gitlab.isc.org/isc-projects/kea/issues. ## Changes The following summarizes changes and important upgrade notes since the previous release (1.6.0 final). ``` 1664. [build] razvan Make sysrepo_config detect installed sysrepo version. (Gitlab #766,!449, git e1a236fa4f4680d3eadade6b5f5a6a6065620a5b) 1663. [build] fdupont Dropped support for Botan 1.x crypto library in Kea as these versions are now end of life. (Gitlab #345,!498, git ba028eee986c0da963754c6fcb74790081557bec) 1662. [bug] marcin Prevent deadlock in the Kea DHCP servers caused by allocating memory in the system signal handler. The issue was found on CentOS 7.6, but could possibly affect Kea running on any other OS. (Gitlab #796,!504, git f858d9d0b63a18370ebb8bd7d1b8250d0c5a1cb5) 1661. [bug] tmark kea-dhcp4 now rejects inbound client messages that have neither a hardware address nor a client identifier. (Gitlab #821,!501, git 60baf65d0c9de384b0da147b50b7fc3180fc54dd) 1660. [func] franek Statistics of the DHCP packets are now initialized upon the server startup. This makes the statistics available for fetching via control channel immediately after the server is started. (Gitlab #755,!503, git f0238d1b6e88dfedaa91029ec3b65e06c14cab34) 1659. [bug] razvan Corrected an issue in the DHCPv4 server logic whereby the user-defined option definitions were not committed which could result in configuration failures when values for such options were specified. (Gitlab #729, !434, git e5b68fb226161dcdef0e4d2d9d03d9bdb95af5e2) ``` Thank you again to everyone who assisted us in making this release possible. If you would like to contribute to ISC to help us continue to make quality open source software, please visit our donations page at https://www.isc.org/donate. We look forward to receiving your feedback.