Description: Indicates whether this is the primary redundant unit or not. If this unit is the primary unit, this object is true. If this unit is the secondary unit, this object is false.

Note that the terms 'primary/secondary' are not synonymous with the terms 'active/standby'. At any given time, the primary unit may be the active unit, or the primary unit may be the standby unit. Likewise, the secondary unit, at any given time, may be the active unit, or the secondary unit may be the standby unit.

The primary unit is given a higher priority or precedence over the secondary unit. In a race condition (usually at initialization time) or any situation where the redundant units are unable to successfully negotiate activity between themselves, the primary unit will always become the active unit and the secondary unit will fall back to standby. Only one redundant unit can be the primary unit at any given time.

The algorithm for determining the primary unit is system dependent, such as 'the redundant unit with the lower numeric unit id is always the primary unit.'