What's the best Kibana multi tenancy free open source project?

Disclaimer: I work for floragunn, makers of Search Guard.

The only real way to separate dashboards and visualizations based on users/tenants is to place them in separate Kibana indices. This is what both Search Guard and Own Home does.

The reason for this is how Kibana works internally: Out of the box, Kibana will place all of these objects in one global Kibana index, shared by all users. Since Kibana itself has no notion of users, roles or tenants, the only way to do it is to intercept the calls to the Kibana index, and rewrite the index name based on the provided user/role information.

• Search Guard does this directly on Elasticsearch level, so the tenant dashboards are separated even if you access Elasticsearch directly.
• Own Home does that on Kibana level, but the effect/outcome is basically the same.
• X-Pack does not have multi-tenancy for Kibana, so there's no separation of dashboards, only access control on Elasticsearch. Same is true for ReadOnly Rest.

One other option you have is to use the Red Hat OpenShift platform. They have an Elasticsearch plugin that is integrated with the Community Edition of Search Guard, and their own Kibana multi-tenancy module. As far as I know, this plugin is completely free.