8. C300 Redundancy operation
8.4. Synchronization states
R500
April 2017
Series 8 C300 Controller User's Guide
Honeywell
211
RDNCMPT
Parameter
State
Description
PLATFORM
Incompatible
Mismatched compatibility types (that is, different
platform firmware).
NodeNumber
Incompatible
Device Indexes of potential redundant partner modules
are not properly configured as consecutive odd/even
pair.
HardwareType
Incompatible
Mismatched factory data (that is, different platform
hardware).
FirmwareType
Incompatible
Mismatched compatibility types (that is, different
platform firmware).
MessageFmt
Incompatible
The partner compatibility message format is undefined
or not supported.
PartnBootFmw
Incompatible
The partner module is executing from boot firmware
(for example, partner is in the Alive, Ready, or Fail
State). To be compatible, both partners must be
executing from application firmware.
8.4
Synchronization states
The RDNSYNCSTATE parameter indicates the controller's synchronization state. Given
a redundant controller pair, synchronization is the act of transferring configuration and
execution data from the primary controller to the secondary so that the secondary has the
same information as the primary when it is needed to transition into the primary role.
Synchronization is only possible for a compatible redundant controller pair; when a
compatible partner is found, the controller transitions from the 'No Partner State' to the
'Partner Visible State.' Initial-sync is the act of performing first time transfer of
synchronization data; during this time the controllers are in the 'Sync in Progress' State.
The redundant controller pair enters the 'Synchronization Maintenance State' upon initial-
sync completion. While in the Synchronization Maintenance State, the secondary is a
viable replacement for the primary controller, and only that configuration data that is
changed and the control data that changes as a consequence of primary controller
execution is synchronized to the secondary controller.