C135 PCS 7 (PCS7)
6C
6 Cielo Ciencia y Tecnología
·Publicada en C135 PCS 7 (PCS7)

Monitoring Redundant SIMATIC BATCH Server Pair Availability in WinCC and External NMS

Monitoring Redundant SIMATIC BATCH Server Pair Availability in WinCC and External NMS

To monitor the redundancy status and Master/Standby role of a SIMATIC BATCH server pair, query the system tags and asset management interfaces integrated into PCS 7 and WinCC. In WinCC OS runtime, the health of redundant partner applications (including SIMATIC BATCH) is reflected in internal system tags: @RedundantServerState (1=Master, 2=Standby, 3=Fault, 4=Standalone) and @PRF_REDUNDANCY_IS_SYNCHRONIZED (1=Synchronized, 0=Not Synchronized). In PCS 7 Maintenance Station (Asset Management), query the tag SNMP_SERVER.MaintenanceState. For external Network Management Systems (NMS) such as PRTG or Zabbix, query the SIMATIC NET SNMP OPC Server or poll the Windows service status of bfserver.exe and bfsched.exe via SNMP.

Table of Contents

Executive Summary

In regulated pharmaceutical, chemical, and food & beverage facilities running SIMATIC BATCH in high-availability redundant configurations, monitoring server health is essential to prevent batch abortion, recipe desynchronization, and data loss. While WinCC OS redundancy is readily monitored via native system tags like @RedundantServerState, plant engineers and IT infrastructure administrators frequently need to expose the operational status of the redundant SIMATIC BATCH server pair to external Network Management Systems (NMS) or centralized SCADA dashboards. Because SIMATIC BATCH operates as an integrated redundancy application registered within the WinCC redundancy framework, its availability can be tracked via internal WinCC performance tags, Maintenance Station SNMP objects, or direct Windows service monitoring.

Architecture and Fundamental Mechanics

The redundancy and diagnostic architecture of SIMATIC BATCH relies on multi-layer state synchronization:

  1. SIMATIC BATCH Redundancy Mechanics: A redundant BATCH server pair consists of a primary Master server and a Standby server. The active Master coordinates batch execution, recipe steps, and controller allocations via the Batch Control Server service (bfserver.exe) and Batch CDV Server (bfcdv.exe). The Standby server runs in hot standby, mirroring recipe states and batch history through real-time database replication over the terminal bus.

  2. Integration with WinCC Redundancy Framework: SIMATIC BATCH registers itself as a redundant application with the WinCC Redundancy Manager (RedundancyControl). Consequently, BATCH health is factored into core WinCC redundancy tags:
    - @RedundantServerState: Reports the local node role: 1 = Master, 2 = Standby, 3 = Fault, 4 = Standalone.
    - @PRF_REDUNDANCY_IS_SYNCHRONIZED: Returns 1 only when both WinCC archives and SIMATIC BATCH databases are fully synchronized.
    - @PRF_REDUNDANCY_VALIDATION: A dynamic health score evaluating terminal bus connectivity, network adapter reachability, and application heartbeats. A failure in bfserver.exe drops the validation score, triggering an automatic server failover.

  3. Maintenance Station (Asset Management) SNMP Architecture: When PCS 7 Maintenance Station (MS Standard) is deployed, server PC hardware and core services are monitored via SNMP. The internal tag SNMP_SERVER<ComputerName>.MaintenanceState reflects overall server health, flagging maintenance requests if BATCH redundancy replication fails.

  4. External NMS Integration: External IT monitoring software (e.g., PRTG Network Monitor, Zabbix, Nagios) cannot read internal WinCC memory tags directly. Instead, external systems monitor BATCH redundancy by:
    - Querying the SIMATIC NET SNMP OPC Server for hardware and network interface availability.
    - Polling Windows Service SNMP OIDs for the operational states of bfserver.exe and bfsched.exe.
    - Reading WinCC tags via OpenPCS 7 OPC UA / OPC DA interfaces.

Step-by-Step Implementation Procedure

Configure BATCH redundancy monitoring across WinCC and external network management tools using the following steps:

Method 1: Monitoring via WinCC Redundancy Tags in Graphics

  1. Open WinCC Graphics Designer on the OS client or server.
  2. Place an I/O Field or Status Display on an administrative overview screen.
  3. Bind the object to the internal system tag @RedundantServerState.
  4. Configure dynamic text formatting:
    - Value 1 -> 'Master Server (Active)'
    - Value 2 -> 'Standby Server (Synchronized)'
    - Value 3 -> 'Redundancy Fault / Split-Brain'
    - Value 4 -> 'Standalone Operation'
  5. Bind a companion status indicator to @PRF_REDUNDANCY_IS_SYNCHRONIZED to confirm replication health.

Method 2: Maintenance Station SNMP Tag Inspection

  1. In SIMATIC Manager Plant View, ensure the BATCH servers are integrated into the Maintenance Station Plant Hierarchy.
  2. Open the Maintenance Station WinCC project.
  3. Locate the generated tag SNMP_SERVER<ServerName>.MaintenanceState in Tag Management.
  4. Connect this tag to the plant asset dashboard to visualize diagnostic status according to NAMUR NE107 standards.

Method 3: Exposing BATCH Redundancy to External NMS via SNMP / OpenPCS 7

  1. On both BATCH servers, open Windows Services (services.msc) and enable the SNMP Service.
  2. Under SNMP Service Properties -> Security, configure the read-only community string (e.g., public) and add the NMS IP address.
  3. In the external NMS (e.g., PRTG):
    - Add the BATCH Server primary and secondary IP addresses.
    - Create a Windows Service Monitor sensor targeting Batch Server Service (bfserver.exe).
    - Configure a ping/reachability sensor targeting the redundancy heartbeat adapter.
  4. Alternatively, deploy OpenPCS 7 on the OS/BATCH server to expose @RedundantServerState and @PRF_REDUNDANCY_IS_SYNCHRONIZED directly to the NMS via secure OPC UA.

Verification

Verify the redundancy monitoring system under operational and fault conditions:

  1. Normal State Verification: Observe the WinCC dashboard on both servers. Confirm that the primary server displays @RedundantServerState == 1 (Master) and the secondary displays @RedundantServerState == 2 (Standby), with @PRF_REDUNDANCY_IS_SYNCHRONIZED == 1.

  2. Simulated Failover Test: Gracefully stop the Batch Server Service on the active Master server. Confirm that:
    - The Standby server immediately transitions to @RedundantServerState == 1 and assumes control of active batches.
    - The external NMS raises an immediate alert indicating the primary service stopped.
    - WinCC logs an alarm indicating redundancy failover.

  3. Re-synchronization Audit: Restart the stopped service. Confirm that the servers re-synchronize, database replication completes, and @PRF_REDUNDANCY_IS_SYNCHRONIZED returns to 1.

Limitations and Operational Precautions

Do not rely solely on ICMP network pings to monitor BATCH server health: a server PC may respond to network pings while its internal bfserver.exe process is deadlocked or its database replication is broken. Always monitor application-level tags or Windows service states. Furthermore, when deploying OpenPCS 7 for external NMS access, verify licensing requirements with an authorized Siemens distributor or the Siemens Industry Mall.

Engineer FAQ

Is there a dedicated tag named @BatchRedundantServerState?

No. SIMATIC BATCH integrates directly into the WinCC redundancy engine, meaning its redundancy status is reflected within the standard WinCC system tags @RedundantServerState and @PRF_REDUNDANCY_IS_SYNCHRONIZED.

What values does @RedundantServerState return?

Value 1 indicates Master, 2 indicates Standby, 3 indicates Fault condition, and 4 indicates Standalone operation.

What core Windows services execute SIMATIC BATCH?

The core services are Batch Server Service (bfserver.exe), Batch CDV Server (bfcdv.exe), and Batch Scheduler (bfsched.exe).

How does SIMATIC BATCH handle split-brain situations?

If terminal bus communication is severed while both servers are healthy, the redundant servers enter a fault state (@RedundantServerState == 3) to prevent dual unsynchronized recipe modifications until communication is restored.

Can external NMS systems query WinCC system tags directly via SNMP?

Standard Windows SNMP cannot read WinCC internal memory tags. External systems must use the SIMATIC NET SNMP OPC Server, OpenPCS 7 OPC UA, or monitor the underlying Windows service executables via standard SNMP OIDs.

Technical References

Related Articles

Related Tags

  • SIMATIC BATCH
  • WinCC Redundancy
  • @RedundantServerState
  • SNMP
  • Asset Management
  • Fault Tolerance
20 respuestas