A runtime Point Management database that holds current data values is maintained on the primary server and duplicated on the secondary server.
The primary Point Manager:
Processes point updates from:
Device Communication and the Virtual Point Process on the primary server
All manual and automatic control functions
Sends updates to the secondary Point Manager.
If device communications processes are running on the primary server, the corresponding processes also run on the secondary server.
While the primary server is the master, the device communication modules on the secondary server operate in standby mode to minimize the impact of redundant data collection on the communications LAN or the programmable controller.
When the primary server terminates, the:
Secondary Point Manager automatically begins receiving its updates from
The Device Communications and Virtual Point Process on the secondary server
All manual and automatic control functions.
Device Communications on the secondary server:
Establishes full communications with the devices and scans all point values.
Reports all point data to the Point Manager.
Important: Applications affected by duplicated point values are not supported.
When the primary server is restarted, resynchronization takes place:
The primary server immediately updates user registration and alarm data from the secondary server while it automatically takes over these functions.
A CIMPLICITY System manager issues a manual command for the primary server to take over point management and device communication.
The primary server:
Collects point data from the secondary server
Takes control of point management and device communication
The secondary server returns to standby mode.
Automatic redundancy operation overview. |