[NIFI-4068] Add first class support for rolling upgrades

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: Core Framework
• Assignee: Unassigned
• Reporter: Matt Gilman
• Created: 14/Jun/17 00:47
• Updated: 14/Jun/17 00:47

Description

We need to add first class support for rolling upgrades. Currently, all nodes need to be upgraded at the same time as our clustering model assumes all nodes are running the same version of the REST API and support the same data model used by that API. Based on which node is the active coordinator, it may be attempting to unmarshal a response from a newer version of NiFi.

Additionally, the introduction of versioned components assumes that all nodes are running the same version of that component. This is necessary since different versions may support different properties, relationships, etc. And depending on the version of NiFi that is the active coordinator, the results to the client could vary (if they unmarshalled successfully).