Siemens SIMATIC S7-1500 System Manual page 120

Advantages of system IP addresses over device IP addresses
• Targeted communication of the communication partner with the primary CPU.
• The S7-1500R/H redundant system can continue to communicate over a system IP address
even if the primary CPU fails.
Configuration example
The figure below shows a configuration in which the S7-1500R/H redundant system
communicates with other devices over the system IP address X2. The other devices are
connected to the S7-1500 redundant system over the X2 PROFINET interfaces.
Figure 5-28
System IP address for communications processors
As of STEP 7 V19, you have the option of expanding S7-1500R/H redundant systems (as of FW
version V3.1) with CP 1543-1 communications processors (as of FW version V3.0). When
extended with CP 1543-1 communications processors, R/H-CPUs support the configuration of
a W1 virtual interface with device and system IP addresses. The communication partners
connected to the CPs communicate with the R/H-CPUs via these IP addresses.
You enable the W1 system IP address in STEP 7.
There is a virtual MAC address for each system IP address.
S7-1500R/H redundant system
System Manual, 01/2024, A5E41814787-AF
Example: Communication of the S7 1500R/H redundant system over the system IP
address X2
System overview
5.4 Communication
119