The documentation is a bit confused on this point... Does Alfresco community 6.0 (deployed using kubernetes) supports clustering?
No - Alfresco community has never and will likely never support full clustering on the application level (at least not in the default bundle provided by Alfresco).
What it may support is running in a Kubernetes cluster as part of the deployment method, but the Repository itself is not clustered with regards to its internal caches. As far as I can see from the source code perspective, all code relevant for the Hazelcast-based inter-cluster communication on the Repository-tier is still not part of the open core. Share itself could always be clustered even in community since the code necessary for that has always been part of the Spring / Alfresco Surf codebase (there is no Enterprise-specific Share artifact).
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