Topic: How to do a redundancy NION system
In Asia, i had some projects using redundancy NION system, some of them are 1 to 1 backup,the others are 1 to more. the technique as follows:
To make a complete automatic backup system with NION, we need work by two steps: the first is auto-changeover to redundancy NION when the primary NION is down, including power failure, DSP stoppage, fan temperature deviant,LAN port communication stoppage and other you think turn to backup NION in need. the second step is changeover the CM-1 port to backup NION's this part needs another program to switch.
1\NION's changeover: put a Project Link device with Blinker(act heartbeat) and CM-1 status and fan temperture meter etc. on the primary NION side, and then put a script on the redundancy NION side to judge whether to trigger changeover action, if yes the Script will be switch bundle number from 0 to valid number
2\CM1's changeover: using a third party emulated Nware program with a SNMP module python script to monitor the redundancy NIONODE status once it starts running the script will be sending a command to change parameter of Request_Bundle_Priority of redundancy CM1 from default 0x1010 to higher. note that Request_Bundle_Priority is different with Priority in NWare CM1 advanced configurable table. please refer to CM1 Programmer's Reference manual P103 about txPriority description.
NOTE: for redundancy design, all NIONODE are pulled out the analog I/O card/s, if you want to use them be careful of impedance of input card and relay security of output card.
about 1 to more redundancy design, if someone needs it I'll post other topic.