Problem Statment
Currently, on EVE software module, ZedAgent is responsible for top level orchestration, basos upgrade validation, cloud connectivity for configuration/status.
In the whole EVE node boot up process, ZedAgent and associated modules are spawned, only after network connectivity(through nim, waitfor address) and device registration (zedclient).
For baseos upgrade validation, this leaves a gap between node boot up and real baseos upgrade transition process invocation in zedagent. Any failure inbetween, the device boot up until zedagent starts, may lead to device being struck in some indefinite state and may turn the device to a non-functional unit.
Proposal
The zedagent module will be broken-up. The base of validation and over all connectivity and device health will be managed by DevAgent. The DevAgent will be one of the first modules to be spawned along with ledmanager, and will be persistent for the whole lifetime of the EVE node. The ZedAgent will be only responsible for cloud connectivity and configuration parsing and status/metrics publication. The baseos upgrade validation will be covered by DevAgent module, covering all the intermediary state for the device boot up.
