The gRPC service name for the health check. The value of grpcServiceName has the following meanings by convention:
The port number for the health check request. Must be specified if portName and portSpecification are not set or if port_specification is USE_FIXED_PORT. Valid values are 1 through 65535.
Port name as defined in InstanceGroup#NamedPort#name. If both port and port_name are defined, port takes precedence.
Specifies how port is selected for health checking, can be one of the following values: