Upgrade of Neo4j service to 5.26 LTS

It is recommended to upgrade the Neo4j service to version 5.26 LTS, as this version contains important security updates and bug fixes.

Neo4j is currently only used for the Test Data Finder component in XDM. If you are not using this component at present, the Neo4j container is obsolete and should be removed from your Docker-based installation, if it exists. Then, also the environment variables spring.data.neo4j.uri, spring.data.neo4j.username and spring.data.neo4j.password must be removed from the core-server and dataflow-server, if used.

Note that a possibly existing Neo4j volume mount xdm-neo4j should be deleted to free up disk space, as it is no longer needed.

For Kubernetes installations, the Neo4j container should be disabled in the HELM chart.

Upgrade instructions

Manually upgrading the Neo4j service to the LTS version 5.26 is necessary for installations managed via Docker Compose or other Docker-based methods, such as Podman.

After updating your Docker-based installation, make sure to migrate the mounted Neo4j volume to ensure that the new version is used, as described below.

Kubernetes installations are automatically updated to the new version and do not require any manual migration.

Docker installations

For installations managed via Docker Compose or other Docker-based methods, such as Podman, the version of Neo4j must be updated to 5.26 in your docker compose file. The following example shows the required changes:

neo4j:
    image: docker.ubs-hainer.com/neo4j:5.26

Additionally, several properties have been renamed and marked as deprecated in the new Neo4j version. These properties should be updated in your docker compose file, if used. Beneath others, the initial and maximum heap size properties have been renamed and should be updated as follows:

Table 1. Renamed properties
Previous name	New name
`NEO4J_dbms_memory_heap_max__size`	`NEO4J_server_memory_heap_max__size`
`NEO4J_dbms_memory_heap_initial__size`	`NEO4J_server_memory_heap_initial__size`

In Neo4j Version 5.20, a usage reporting system that sends anonymous usage data to Neo4j has been introduced. This can be disabled by setting the following environment variable:

neo4j:
    environment:
        - NEO4J_dbms_usage__report_enabled=false

The new Neo4j version 5.26 is run per default with root user privileges. It is recommended to change the user to the non-root user neo4j for security reasons. This can be done by adding the following line to your docker compose file:

neo4j:
    user: "7474:7474"

Migrate Neo4j data

When Neo4j is needed for the Test Data Finder and migrated to LTS version 5.26, it is necessary to recreate the data from the Data Indexing tasks. To do this, first delete the mapped Neo4j volume mount before restarting XDM.

The name of the Neo4j volume mount can be found in your docker compose file, for example:

neo4j:
    volumes:
        - ./xdm-neo4j:/data

Please make sure to delete the mounted folder for Neo4j.

Afterward you can run the Data Indexing tasks to recreate the data in the Neo4j database.