While we’re committed to open source, we also can’t ignore the realities of business. We need to be able to pay developers to continue to drive the InfluxDB project forward. As a result, we’ve decided to build future clustering functionality as closed source software. Future versions of the open source InfluxDB will focus on providing the best experience and performance as a standalone server. Clustering and high availability functionality will be available as part of our Influx Enterprise offering, which will be available in the coming months.
Source: Update on InfluxDB Clustering, High-Availability and Monetization | InfluxData