Dear Experts,

We are currently facing an issue related to our redundant WinCC system.
Our setup includes:

• Two SIMATIC IPC547J units configured as redundant WinCC servers
• One SIMATIC IPC527G unit configured as a WinCC Client
• Two redundant S7-1517H PLCs

We are conducting a test to verify the redundancy functionality of the system.

Test Scenario:

• We disconnected the Ethernet cable from Server A (which was the current primary).
• The WinCC Client remained connected, suggesting that Server B (previously the backup) had taken over as the primary.

However, we noticed an issue regarding the system redundancy tag @RM_MASTER_NAME:

1. (Case 1)
   At the time of switchover, the @RM_MASTER_NAME tag on Server B did not change from "SERVER_A" to "SERVER_B" immediately.
   It only updated after reconnecting the Ethernet cable of Server A.
    
2. (Case 2)
   In some other tests, even after reconnecting the Ethernet cable of Server A, the @RM_MASTER_NAME tag still did not update on Server B.
   As a result, we cannot determine whether a proper server switchover occurred or not.
    

Based on our understanding, if the primary server is switched over, the system tag @RM_MASTER_NAME should immediately reflect the new master server name (e.g., change from "SERVER_A" to "SERVER_B"). Since this did not occur consistently, we believe this may be an abnormal behavior.

We would highly appreciate your support in verifying and explaining this behavior.

Thank you in advance for your assistance.

Best regards,

Hi Murof,

I have not installed any updates on the 2 WinCC Servers.

Currently it is original WinCC V8.0.

Thanks & Best regards,

Murof

Hello TranDuc96

Which Update do you use for your WinCC V8.0?

Do you have installed the latest available updates on all systems?

https://support.industry.siemens.com/cs/de/en/view/109818723

Bye Murof