Hi,

i try to setup EMQX v5.8.4 open source cluster with 'Durable Session' enabled but all nodes failed to start with this error:

2025-01-10T08:31:21.082998+00:00 [error] failed_to_check_schema: emqx_conf_schema 2025-01-10T08:31:21.085937+00:00 [error] #{reason => integrity_validation_failure,result => {error,<<"cluster discovery strategy must be 'singleton' when durable storage backend is 'builtin_local'">>},kind => validation_error,validation_name => validate_durable_sessions_strategy}

I use the docker compose file file from the documentation (https://docs.emqx.com/en/emqx/latest/deploy/install-docker.html#use-docker-compose-to-build-an-emqx-cluster) just with the additional environment variable "EMQX_DURABLE_SESSIONS__ENABLE=true"

It works in single node mode when i set EMQX_CLUSTER__DISCOVERY_STRATEGY=singleton.

That brings me to the question, is the 'Durable Session' feature in cluster mode available in the open source version?

The documentation is a little bit confusion about this because on top of this page https://docs.emqx.com/en/emqx/latest/durability/durability_introduction.html is mentioned that 'Durable Session' is an Enterprise feature only but later on same page in section Durable Sessions is mentioned that the HA replica feature is an enterprise feature but 'Durable Session' is available in in the open source version just without the replica feature.

What is true? Or have I misunderstood something?

Thank you for your support and have a good day!