We have released a new version of the Axon Server.
Release 2026.0.0
Context migration to DCB
Axon Server 2026.0 offers a way to convert existing event store contexts to the DCB format.
This allows you to migrate contexts with existing data to the new format and make use of the DCB features that Axon Framework offers.
Learner node type
Learner nodes replicate the event store and participate in replication groups without voting in leader elections or commit quorums.
This change is invisible for users but improves safety of cluster topology changes with running event transformation or context migrations.
This enables safe capacity expansion: add a new node starts as a learner to catch up on replication, then it gets promoted once it has replicated sufficient data.
New licensing model
Axon Server 2026.0 introduces an updated licensing model:
- Platform License V2 with gRPC-based license fetching
- Axon Server can act as a license source for connected client applications, removing the need to distribute license files to each node separately
- Throughput-based limits are enforced as part of the license
gRPC improvements
Internal gRPC thread pools have been split to separate threads for client-facing and internal cluster communication, reducing the risk of client load impacting cluster stability.
gRPC request tracking metrics have been added for better observability.
RAFT improvements
- Log replication tasks now run in a dedicated executor, reducing interference with other cluster operations
- RAFT log inconsistencies are detected and reported at startup more eagerly, following a fail-fast mentality
- Certain configuration changes are rejected in mixed-version clusters, preventing incompatible changes during rolling upgrades
Breaking changes and removals
- Java 21 is now the minimum supported version.
- The legacy UI, originally superseded in 2024.0, has been removed.
- Analytics node roles are deprecated and replaced by the stand-alone analytics application.
Existing deployments continue to work, but analytics node support will be removed in a future release. - OAuth2 and LDAP extensions are no extensions, their functionality is now part of the core product.
- Legacy metric names (the pre-2023.2 naming scheme) are now disabled by default.
Other improvements
- Legacy EventStore API is now supported on DCB contexts.
- Link to the Swagger UI added to the administration interface (icon in the top right)
- Performance improvements: consistent hash routing, query routing metric caching, reduced database load from gRPC threads, memory leak fix in event storage engine shutdown
- Changed ToS notice to reflect latest version
Bug fixes
- Fix startup issue during node restart after install snapshot
- Fix install snapshot handling for DCB contexts (tag replication, _admin event store, flow control)
- Fix persistent stream ghost connections and NPE
- Fix broken cache after context configuration changes
- Fix deserialization issues in context data and the application REST controller
- Fix throughput statistics output
- Fix node version reporting during rolling upgrades
- Fix to prevent cluster initialization with invalid configuration
- Fix SequenceValidationStreamObserver being skipped on DCB contexts
- Fix column selection box in the search page
- Fix scrolling in list view on Nodes and Applications pages
- Fix NPE when re-adding a previously removed node
- Dependency updates to address security vulnerabilities
The latest version can be downloaded from the download page.