This occurs for all nodes of 8.0 version as they contain old nailgun agent. Thus, it is impossible to do anything with old clusters - this makes Fuel unusable after upgrade and this is a major regression in functionality. Also, updating nailgun agent is not a solution here as old 8.0 nailgun-agent nodes should not contain new feature-related code.
This occurs for all nodes of 8.0 version as they contain old nailgun agent. Thus, it is impossible to do anything with old clusters - this makes Fuel unusable after upgrade and this is a major regression in functionality. Also, updating nailgun agent is not a solution here as old 8.0 nailgun-agent nodes should not contain new feature-related code.