Desired state in a fleet
The fleet store gives desired state a shared home, a signed history, and a per-machine apply record.
Declare
Use the four layers:
fleet.yaml
os/<platform>.yaml
groups/<group>.yaml
hosts/<machine>.yaml
Each item resolves to one effective value for the machine. Maps merge by key; scalar values replace as units; absent removes an item from the effective set.
Review
The receiving host reviews the resolved digest and its provenance. Canary members adopt a changed digest first; downstream members read the canary’s signed journal outcome after the policy wait.
Apply
The host applies the item through its owning manager, writes applied/<machine>.yaml, and records the result in journal/<machine>/. A held item keeps its prior applied value and carries a named alert.
Explain
roundhouse fleet-explain <machine> plugins.<name>
The output shows the winning layer and the value that produced the digest.
Proof point
The store and convergence sources describe the four-layer fold, canary release, item digest, journal outcome, and fleet-explain path. Sources: roundhouse/docs/store.md and roundhouse/docs/convergence.md.
Next: see fleet scaling or read trust.