This table lists the major feature differences for different releases of Kea. A "✔︎" in the table below indicates that feature is present in that branch. When all currently supported versions of Kea have the feature, we remove the row (because there is no difference to highlight).
This list does not include many smaller changes, including changes in existing features or minor new features. For more detail, we recommend checking release notes. The release notes for the first release on a new stable branch (e.g. 3.0.0) include significant changes since the last stable version.
| Feature | Kea 3.0 Stable | Kea 2.6 Stable | Kea 2.4 EOL | Kea 2.2 EOL | Kea 2.0 EOL | Kea 1.8 EOL |
|---|---|---|---|---|---|---|
| Access Control (see also TLS Support) | ✔︎ | ✔︎ | ✔︎ | new RBAC hook | basic local authentication | |
| Address Allocation | iterative, random, free leases queue offer-lifetime allows early allocation |
iterative | iterative | iterative | ||
| Bulk Leasequery | ✔︎ | new command and query added | new hook lib, DHCPv4 & DHCPv6 | |||
| Cache Threshold - Minimize Updates to Existing Leases | ✔︎ | ✔︎ | ✔︎ | ✔︎ | X | |
| Client Class Tagging | ✔︎ | - | - | - | - | - |
| Database - Cassandra Backend | - | - | - | REMOVED | deprecated, will be removed in 2.2 | ✔︎ |
| Database - Configuration Backend Using PostgreSQL | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ||
| Database - Reconnect | ✔︎ | ✔︎ | ✔︎ | ✔︎ | updated in 1.9.4, see `on-fail` logic for how to handle failures | ✔︎ |
| DDNS Controls | ddns-ttl, ddns-ttl-min, ddns-ttl-max, per-pool DNS parameters | ✔︎ | `ddns-ttl-percent` | new DDNS-Tuning hook | ✔︎ | ✔︎ |
| Drop Class for Clients with Reservations | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | |
| High Availability | ✔︎ | hub-and-spoke model for multiple HA relationships | ✔︎ | ✔︎ | now multi-threaded | paged updates |
| Host Reservations Mode - Global | reservations in-subnet enabled by default | reservations in-subnet enabled by default | reservations with address out-of-subnet overridden | options/modes changed, `early-global-reservations-lookup` | ✔︎ | ✔︎ |
| Host Reservations Mode - Multiple | ✔︎ | auto-generated subnet IDs removed | empty host reservations | `reservations-lookup-first` | separate controls for global, in-subnet, or out-of-pool reservation modes | |
| Lease Migration Between Backends | ✔︎ | ✔︎ | ✔︎ | leases can now be exported from one backend and imported into another | ✔ | |
| Lease-lifetime | ✔︎ | ✔︎ | new DHCPv4 offer-lifetime parameter, DHCPv6 preferred lifetime is calculated as 0.625 * valid-lifetime unless explicitly specified, or if specified value > valid lifetime affinity for release leases |
✔︎ | ✔ | preferred and valid lease lifetimes added to client classes |
| Libreload | - | - | REMOVED | |||
| Meson Build System | ✔︎ | - | - | - | - | - |
| Multiple MAC Reservations for the Same IP | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | |
| Multithreading Support | ✔ MT enabled by default | ✔ MT enabled by default | ✔ MT enabled by default | ✔︎ | ✔︎ (added MT for HA, bypassing the CA) | ✔︎ (not including HA) |
| MySQL, PostgreSQL Hooks | ✔︎ | - | - | - | - | - |
| Native HTTP/TLS Support | ✔ | - | - | - | - | - |
| Open Source Hooks | all hooks are open source except the RBAC and Configuration Backend hooks | - | - | - | - | - |
| Options | NTP servers DHCPv6 Option #136 and its associated suboptions as per RFC5908 | new stash-agent option, updated implementation of the DNR option, new classless static route option | multiple vendor options with multiple vivco suboptions and different enterprise IDs multiple instances of DHCPv6 vendor-class and vendor-opts. DNR encrypted DNS options DHCPv4 Option #143 and DHCPv6 Option #136 per RFC8572 `never-send` flag |
✔︎ | ✔︎ (added MT for HA, bypassing the CA) | ✔︎ |
| Statistics | per-pool statistics added | |||||
| Template Classes | ✔︎ | ✔︎ | ✔︎ | |||
| TLS Support | ✔︎ | ✔︎ | ✔︎ | TLS secures connections between Kea and MySQL & PostgreSQL backends | CA can require client identification and can use TLS encryption for client connections | |
| YANG/NETCONF Model Support | ✔︎ | NETCONF model updated, vivso-option support added | updated to libyang 2.x, Sysrepo 2.x | YANG model updated, Sysrepo 1.4 | ✔︎ | ✔︎ |
Kea hook libraries extend the base functionality of the open source Kea DHCP server. The hooks shown below are included in the Kea open source, unless marked below as included in the Premium, Subscriber, or Enterprise commercial packages (for versions prior to Kea 3.0.0).
As of Kea 3.0.0, all hook libraries are now open source except the RBAC and Configuration Backend libraries. Those two remain commercially licensed and are only available with an ISC support subscription. Some of the hooks for Kea version 2.6 are still commercially licensed; administrators wishing to use that version may purchase those hooks on our website at https://www.isc.org/shop/. For more information, please fill out our contact form at https://www.isc.org/contact.
This table lists the versions of Kea and the Kea hook libraries ISC supports, starting with Kea 3.0.0.
The table at the bottom of this page details the commercially licensed and open source hook libraries through Kea 2.6.
| Hook Libraries | Kea 3.0 Stable - Open Source | Kea 3.0 Stable - ISC Subscriber-Only |
|---|---|---|
| BOOTP (RFC 1497) | ✔︎ | |
| Class Commands | ✔︎ | |
| Configuration Backend Commands | ✔︎ | |
| Database Backend for MySQL | ✔ | |
| Database Backend for PostgreSQL | ✔ | |
| DDNS Tuning | ✔︎ | |
| Flexible Identifier | ✔︎ | |
| Flexible Options | ✔︎ | |
| Forensic Logging | Syslog support | |
| GSS-TSIG | ✔︎ | |
| High Availability | HA listener restrict-commands configuration flag defaults to true | |
| Host Cache | ✔︎ | |
| Host Commands | ✔︎ | |
| Lease Commands | ✔︎ | |
| Leasequery | ✔︎ | |
| Limits | ✔︎ | |
| Ping Check | ✔︎ | |
| RADIUS Server Support | ✔︎ | |
| Role-Based Access Control | ✔︎ | |
| Run Script | ✔︎ | |
| Statistics Commands | ✔︎ | |
| Subnet Commands | subnet4-select-test, subnet6-select-test, and subnet4o6-select-test added | |
| User Check (example hook) | ✔︎ |
This table lists the versions of Kea and the supported Kea hook libraries, for each version prior to Kea 3.0.0.
| Hook Libraries | Kea 2.6 Stable | Kea 2.4 EOL | Kea 2.2 EOL | Kea 2.0 EOL | Kea 1.8 EOL | Premium package | Subscriber package | Enterprise package |
|---|---|---|---|---|---|---|---|---|
| BOOTP (RFC 1497) | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | |||
| Class Commands | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | + | + | |
| Configuration Backend Commands, requires either Configuration Backend for PostgreSQL or Configuration Backend for MySQL | new global parameters added | ✔︎ support for PostgreSQL backend, options preserved from client classes in cfg backend |
support for client-classes added | ✔︎ | ✔︎ | + | + | |
| DDNS Tuning | ✔︎ | ✔︎ | ✔︎ | + | + | + | ||
| Flexible Identifier | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | + | + | + |
| Flexible Options | ✔︎ | ✔︎ | new CSV-format, support for sub-options | ✔︎ new | ||||
| Forensic Logging | ✔︎ | now records whether the lease change is an administrative action or an automated HA update | added timestamp format | configurable with expressions | ✔︎ | + | + | + |
| GSS-TSIG | ✔︎ | ✔︎ | perform GSS-TSIG updates via Kerberos | + | + | |||
| High Availability | ✔︎ | ✔`max-rejected-lease-updates` added | ✔︎ | significantly updated for better performance with MT, CA bypass, added communication-recovery state, delayed updates, improved DHCP enable/disable | ✔︎ | |||
| Host Cache | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | + | + | |
| Host Commands | ✔︎ | `reservation-get-by-address`, `reservation-update` added | subnet-id parameter is now optional | lease4(6)-get-by-clientid(duid, hostname, hwaddress) | reservation-get-all, reservation-get-page | + | + | + |
| Lease Commands | ✔︎ | ✔︎ | ✔︎ | lease4-write and lease6-write new lease conflict status codes |
lease lifetimes based on client class | |||
| Leasequery | ✔︎ | added support for DHCPv6 Bulk Leasequery (RFC 5460)and DHCPv4 Bulk Leasequery (RFC 6926) using the memfile lease backend | ✔︎ | ✔︎ | ✔︎ | + | + | |
| Limits | ✔︎ | ✔︎ | new hook limits leases per second, leases per class | + | + | |||
| MySQL Configuration Backend | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | |||
| Performance Monitoring | ✔︎ | |||||||
| Ping Check | ✔︎ perform a ping check of a candidate IPv4 address prior to offering it | + | + | |||||
| PostgreSQL Configuration Backend | ✔︎ | ✔︎ | ✔︎ | |||||
| RADIUS Integration | multi-threading enabled | ✔︎ | RADIUS subnet selection added | ✔︎ | cache-size, cache-get-by-id | + | + | |
| Role-Based Access Control | ✔︎ | ✔︎ | + | |||||
| Run Script | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | |||
| Statistics Commands | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ | |||
| Subnet Commands | ✔︎ | ✔︎ | ✔︎ | ✔︎ | subnet4-update, subnet6-update | + | + | |
| User Check (example hook) | ✔︎ | ✔︎ | ✔︎ | ✔︎ | ✔︎ |