Values:
STATE_UNSPECIFIED (0):
The state of the instance is unknown.
READY (1):
The instance is active and running.
STOPPED (2):
The instance is stopped. Instance name and IP
resources are preserved.
CREATING (3):
The instance is being created.
DELETING (4):
The instance is being deleted.
MAINTENANCE (5):
The instance is down for maintenance.
FAILED (6):
The creation of the instance failed or a
fatal error occurred during an operation on the
instance. Note: Instances in this state would
tried to be auto-repaired. And Customers should
be able to restart, update or delete these
instances.
BOOTSTRAPPING (8):
Index 7 is used in the producer apis for ROLLED_BACK state.
Keeping that index unused in case that state also needs to
exposed via consumer apis in future. The instance has been
configured to sync data from some other source.
PROMOTING (9):
The instance is being promoted.
