Rockwell Automation 1756-RMxx ControlLogix Enhanced Redundancy System User Manual - Manual (Page 79)

Rockwell Automation Publication 1756-UM535D-EN-P - November 2012 79
Configure the EtherNet/IP Network Chapter 4
When an enhanced redundancy system begins operating, the primary
EtherNet/IP communication module uses the IP address assigned during initial
configuration. The secondary EtherNet/IP communication module
automatically changes its IP address to the next highest value. When a switchover
occurs, the EtherNet/IP communication modules swap IP addresses.
For example, if you assign IP address 192.168.1.3 to both EtherNet/IP
communication modules in a partnered set, on initial system operation, the
secondary EtherNet/IP communication module automatically changes its IP
address to 192.168.1.4.
This graphic shows a partnered set of EtherNet/IP communication modules
after system operation begins.
Figure 18 - EtherNet/IP Communication Modules’ IP Addresses After System Operation Begins
This graphic shows the partnered set of EtherNet/IP communication modules in
RSLinx Classic software after system operation begins.
Figure 19 - IP Addresses in RSLinx Classic Software
CH2 CH1 OK CH2 CH1 OK
Primary Chassis Secondary Chassis
IP Address: 192.168.1.3 IP Address: 192.168.1.4
TIP Do not assign IP addresses to EtherNet/IP communication modules outside the
partnered set to values that conflict with those used in the partnered set.
In the previous example, the partnered set uses 192.168.1.3 and 192.168.1.4.
Use 192.168.1.5 or higher for all EtherNet/IP communication modules outside
the partnered set.