Duplicate IP Address Checking
Original instructions
About us
Introduction
Each Quantum module has a single IP address. The address conflict detection algorithm (also called duplicate IP checking) is performed based on the status (link up, link down) of the ports.
Link Down
These conditions apply when links are lost:
Link Status
Description
A transition has occurred from one connected link to all links down.
When no module port is connected to a cable (all links are down), all services are reset. For example, I/O connections, Modbus connections, and explicit EtherNet/IP connections close, but low-level network services (like RSTP or switches) are not affected. The updated Net Status LED indicates the status.
There is one link down and at least one connected link.
There is no impact on services that are running in the module.
Link Up
These conditions apply when links are added:
Link Status
Description
A transition occurred from an unconnected link to a connected link.
A duplicate IP check is performed:
  • no duplicate: All services start.
  • duplicate: I/O services stop. The 140CRA31908 module gets new configuration and downloads the IP configuration again. The system goes to default IP and I/O modules are set to fallback mode.
A transition has occurred from at least one connected link to an additional connected link.
A duplicate IP check is performed:
  • no duplicated: All services continue.
  • duplicate: All services stop.
NOTE: The updated Net Status LED indicates the status.