In Reply to: Infi90 NPM (redundant network processing modules) failover posted by walter graham on 03/03/03 at 3:30 PM:
As I am not sure what type of Engineering Tools you are using, meaning SCAD, WinCAD or Composer, each has the ability to select Inspect. A note of interest. Composer 4.0 will shown both the Primary and Redundant (Backup) NPM's as both BACKUP. This is a known problem and will be addressed in the Service Pack.
This window provides information on modules addressed on the Controlway. Addresses 0 to 31 are available.
For the NIS/NPM, only the Primary and Redundant (Backup) NPM's are shown. Other modules like MFPxx or BRCxx may also be shown.
As you have Redundancy in NPM's it is possible to see addresses 0 and 1, where the Primary is 0 and redundant is 1.
If you select the Status Report in the Inspect window, you will see many line statements. Of interest are the Primary if is see's the Backup NPM. If it does, then it will say YES. This is important because if it does not, then there are a number of possible problems.
As you are not in the error mode, meaning that neither NPM has a solid Red Status led, then the Redundancy link cable connecting the NPM's together on the MMU is in place and working. Also you have properly addressed the Primary NPM as 0 and the Backup as 1.
When you see the NPM's in your Inspect Window, please make sure that the Firmware revisions are the same. If not, they may work OK, until the Redundant switches over and becomes the Primary. The likely result will be that both NPM's are failed. The firmware versions must the same.
For a 100 percent assurance of proper failover, well, given that all the above conditions are True, you can expect a proper failover. Perhaps during your next shutdown period, you can schedule redundancy testing of NPM's and other modules that are redundant.
I trust that this has helped. Do contact me if you have further questions.