[Kea-announce] Kea 1.7.8, a new development release of Kea, is now available
mcnally at isc.org
Wed May 27 08:51:55 UTC 2020
Internet Systems Consortium is pleased to announce the release of Kea 1.7.8.
Kea releases are divided into two branch sequences:
1) A current stable branch (currently 1.6.x) which receives only important
bug fixes and is otherwise feature-stable, and
2) An experimental development branch (currently 1.7.x) where new features
are added and made available for testing during development, before eventually
being included in the next stable release branch.
Kea 1.7.8 is the latest release in the experimental development branch.
# Kea 1.7.8, May 27th 2020, Release Notes
Welcome to Kea 1.7.8, a monthly development release of Kea. As with any
other development release, use this with caution. Development releases
are not recommended for production use.
The most significant changes introduced in this version are:
1. **High Availability multithreading**. The HA hook now has
experimental mulit-threading support.
2. **HA backup non blocking**. Active servers no longer wait for lease
update acknowledgments from backup servers.
3. **HA passive backup mode** The new passive-backup mode allows for
running a single active server with a number of backup servers.
4. **Multithreading support improved**. We will be releasing Kea 1.8.0
when the multithreading is complete and stable. This release takes
another step towards that goal.
5. **Congestion-control disabled for multithreading**. Multi-threading
and congestion handling are incompatible. When both are enabled by a
configuration the dhcp-queue-control is silently disabled, when
packet-queue-size is not 0 and the multi-threading packet queue is full
the oldest packet is dropped to make room for a new received one.
## Release Model
The Kea project has a significant production deployment base with users
who are looking for stability, rather than a constant stream of new
"bleeding-edge" features. At the same time, we want to continue
developing the software and add some new powerful, but
difficult-to-implement, features. To meet both of these requirements we
have both Stable and Development branches.
Stable releases are what you would expect: stable, released
infrequently, without new features or significant changes, very
well-tested. These can be identified by an even-numbered major version
number. The current stable release is 1.6.2, with a major version of
1.6, and minor version 2. If we discover important bugs that require
fixing, we may release 1.6.3, but that will be determined on a
case-by-case basis. The next major stable version will be 1.8.0,
followed by 2.0.0 in the future.
Development releases can be easily identified by an odd major version
number: for example, 1.7.7 is a development release. In June 2020 we
expect to release 1.7.8, the next development version. Once 1.8.0 is
out, we will continue our development work with 1.9.0, then 1.9.1, and
Our goal is to make the development release available on the last
Wednesday of each month. There may be exceptions (such as during
holidays), but that's the general plan.
We encourage users to test the development releases and report back
For more details on the plan, see ISC's Software Support Policy at
## 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 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
This text references issue numbers. For more details, visit the Kea
GitLab page at https://gitlab.isc.org/isc-projects/kea/issues.
This version of Kea is released under the Mozilla Public License,
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).
Pre-built ISC packages for current versions of the most popular Linux
operating systems are available at:
The Kea source and PGP signature for this release may be downloaded from:
The signature was generated with the ISC code signing key which is
ISC provides detailed documentation, including installation instructions
and usage tutorials, in the Kea Administrator Reference Manual.
Documentation is included with the installation, at
https://kea.readthedocs.io/en/latest/, 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, a wiki, an 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
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
Professional support for Kea is available from ISC. We encourage all
professional users to consider this option; Kea development and
maintenance are 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
The following summarizes changes and important upgrade notes since the
previous release (1.7.7).
1750. [func] razvan
Refactored HooksManager so that no lazy initialization is
from dhcp processing functions. The function getHooksManager is
1749. [func] fdupont
When the version is a development (vs. stable) one (second
number is odd, e.g. in 1.7.x) a server or agent logs a
warning to dissuade use in production.
1748. [func] marcin
Added two extensions to the HA hooks library. Firstly, the active
servers no longer wait for the lease update acknowledgments from
the backup servers. Secondly, the new passive-backup mode allows
for running a single active server with a number of backup
1747. [bug] fdupont
Multi-threading and congestion handling were made incompatible:
when both are enabled by a configuration the dhcp-queue-control
silently disabled, when packet-queue-size is not 0 and the
multi-threading packet queue is full the oldest packet is dropped
to make room for a new received one.
1746. [bug] fdupont
lease4-add and lease6-add commands now return an error when the
lease already exists.
1745. [bug] fdupont
Made state model and external sockets thread safe.
1744. [func] razvan
Stopping packet processing when changing or reloading
Thank you again to everyone who assisted us in making this release
We look forward to receiving your feedback.
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