Inactive -> Active.

Active -> Inactive.

Inactive -> NotFound.

Stable states.

Special case: This is never returned by probes, since those only include the state of ranges which the node has.

Pending -> Inactive.

Should never be in this state.

Should never be in this state.

The range is active, i.e.

The range has finished being split or joined, has been dropped from all nodes, and will never be placed on any node again.

Special case representing both negative and positive infinity.

ZeroRange is not a valid RangeID.

Meta is a range minus all the state.

RangeInfo represents something we know about a Range on a Node at a moment in time.

Remote represents a service listening on some remote host and port.

Action represents each of the state transitions that ranger can ask a node to make.

Key is a point in the keyspace.

NodeID is the unique identity of a node.

RangeID is the unique identity of a range.