Kea 1.1 Released

Kea 1.1 is available!

We are pleased to announce the availability of Kea 1.1. Kea is ISC’s modern DHCP server, which brings new functionality to the datacenter and to any ISP or enterprise that needs to tie dynamic host control into external provisioning systems.

New features in Kea 1.1 include:

Host Reservations

Kea 1.0 contained limited support for storing host reservations in the database backend. Kea 1.1.0 has expanded that capability, allowing host reservations to be stored in a MySQL or PostgreSQL database. In particular, Kea 1.1.0:

  • Adds host reservation (DHCPv4 and DHCPv6) using the PostgreSQL backend.
  • Adds host reservation for DHCPv6 to the existing MySQL support.
  • Significantly extends the existing host reservation capabilities to include reservations of specific DHCP options, reservations of siaddr, sname, and file fields within DHCPv4 messages, and reservations of multiple IPv6 addresses/prefixes.
  • Allows the MySQL or PostgreSQL host reservation database to be configured read-only, in which case Kea will be able to retrieve reservations from it, but not insert or update existing reservations. This feature is useful when a database (or database view) exists for the particular deployment and the administrator doesn’t want to grant read-write access for security reasons.
Client Classification

In Kea 1.1 the client classification system has been expanded. A class definition contains a name and a test expression of arbitrary complexity; if the test expression evaluates to “true”, the client is a member of that class. A client may be a member of multiple classes and can acquire options from different classes. If the configuration contains multiple definitions for data for an option in two or more of the global, class, subnet, or host entries, the server will choose the definition from the most specific entry.

There are a number of objects and operators available for use in the test expression.

  • Operators include: equal, not, and, or, substring, concat
  • Objects include:
    • literals: string, hexadecimal, IP address, and integer
    • options: existence and content
    • relay options for DHCPv4 and DHCPv6: existence and content
    • subfields within vendor and vendor class options: existence, enterprise-id value and content
    • selected fields from DHCPv4 and DHCPv6 packets
  • Classes may be used to select subnets
  • Classes and class specific subnets may contain option data to serve to clients within that class
Hook Library Parameters

It is now possible to specify parameters for hook libraries in the Kea configuration file. In earlier versions of Kea, hook library authors had to use a external mechanism (such as file of a known name) to pass information across.


RFC7341 defines an architecture that allows dual-stack clients to communicate with a DHCPv4 server in IPv6-only networks. Kea 1.1 introduces support for this mode of operation. It requires running both DHCPv4 and DHCPv6 servers in special mode, where DHCPv6 component does not allocate anything, but decapsulates incoming DHCPv4 messages, sends them to the DHCPv4 server, and then relays back the responses.

Cassandra Database Backend

Kea 1.1.0 has added preliminary support for Cassandra as a database backend. In this release of Kea it can only be used to store lease information; it is not able store host reservations. Cassandra support is currently considered experimental. Use with caution.

MPL 2.0 License

Kea 1.1.0 has been released under the Mozilla Public License, version 2.0.


Professional support for Kea is available from ISC. Free best-effort support is provided by our user community via a mailing list. Information on all of ISC’s public email lists is available here

If you have any comments or questions about working with Kea, please share them on the Kea Users List at

Bugs and feature requests may be submitted via GitLab at

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