Deploying SIMATIC PCS 7 in Virtualized Environments (VMware ESXi on Dell PowerEdge VRTX Chassis)

Deploying SIMATIC PCS 7 V9.0 in a virtualized infrastructure hosted on converged blade chassis—such as the Dell PowerEdge VRTX running VMware ESXi—is technically supported provided the hypervisor and guest operating systems strictly comply with Siemens PCS 7 virtualization release notices. Siemens officially releases OS Clients, Batch Clients, Route Control Clients, Web Servers, OpenPCS 7, Terminal Servers, and redundant OS Single Stations / Servers for virtualized operation on VMware vSphere ESXi. Because VMware abstracts the underlying server hardware, Dell VRTX integrated blade nodes and shared storage operate transparently to PCS 7, provided plant bus network interfaces and storage IOPS latency meet stringent real-time automation thresholds.

Virtualization Principles in SIMATIC PCS 7

Virtualization has transformed industrial process control infrastructure by decoupling automation software from proprietary physical server hardware. By running virtual machines (VMs) on a high-availability hypervisor cluster, industrial plants benefit from centralized backup snapshots, hardware fault tolerance, simplified disaster recovery, and substantial reductions in footprint and power consumption.

In SIMATIC PCS 7, virtualization is officially qualified from version V7.1 SP2 onward, with full maturity achieved in PCS 7 V8.2 and V9.0 under VMware vSphere ESXi. Siemens also provides turnkey virtualized platforms under the 'SIMATIC Virtualization as a Service' (SIVaaS) program. When third-party enterprise hardware is selected, engineers must ensure that real-time communication protocols, hardware clock synchronization, and storage throughput satisfy deterministic DCS operation.

Hardware Abstraction: Dell PowerEdge VRTX and VMware ESXi

The Dell PowerEdge VRTX is a converged infrastructure chassis designed for remote and depot facilities, integrating up to four server nodes (such as PowerEdge M630/M640 blades), shared internal SAS storage (RAID controller), and integrated 1GbE/10GbE network switches into a compact 5U rack or tower enclosure.

Architectural LayerImplementation in Dell VRTXPCS 7 Virtualization RequirementHypervisor SupportVMware vSphere ESXi (e.g., 6.0 / 6.5 / 6.7)Must match exact ESXi release version specified in PCS 7 product noteServer BladesPowerEdge M630 / M640 dual Intel XeonSizing based on 2 vCPUs and 8GB-16GB vRAM per OS Server VMShared StorageIntegrated Shared PERC8 / PERC9 RAIDHigh-throughput SAS/SSD datastore; write latency < 10ms for SQL ServerPlant Bus NetworkVRTX 1GbE internal switch moduleDedicated vSwitch and physical pNIC for SIMATIC ISO / BCE communicationTerminal Bus NetworkVRTX 1GbE internal switch moduleSeparate vSwitch and physical pNIC for WinCC client/server trafficTime SynchronizationHypervisor NTP server / SICLOCKVM clock sync disabled from host; native domain/NTP synchronization used

Because VMware ESXi abstracts the underlying hardware, PCS 7 guest VMs do not interact directly with the Dell VRTX chassis. If the Dell server nodes and shared storage controllers reside on the official VMware Hardware Compatibility List (HCL), the hardware environment is fully transparent to SIMATIC PCS 7.

Siemens Virtualization Release Matrix and Requirements

Siemens publishes strict product release announcements defining which PCS 7 stations and options are qualified for virtualized environments:

Released Software Components (PCS 7 V9.0): OS Clients, OS Single Stations, OS Redundant Server Pairs, Maintenance Station (MS), BATCH Server/Client, Route Control Server/Client, Web Server, OpenPCS 7 / OS Client, WinCC DataMonitor, and Terminal Server.
Virtual Network Configuration: Softnet-IE (BCE) is standard for plant bus communication in virtual machines. Dedicated physical network adapters on the host must be mapped to dedicated virtual switches (vSwitch) for the plant bus to isolate industrial Ethernet traffic from corporate LAN and terminal bus packets.
Storage and Memory Reservations: SQL Server databases running inside WinCC OS Servers demand dedicated resources. Hypervisors must configure 100% memory reservation (no memory ballooning or overcommitment) and dedicated vCPU cores for all OS and BATCH server VMs.

Verification

Execute the following validation procedures when commissioning PCS 7 VMs on a virtualized chassis:

VMware ESXi Health and Latency: In vSphere Web Client, verify that datastore write latencies remain consistently below 10 milliseconds during peak Tag Logging and Alarm Logging archive write cycles.
Simatic Shell and Multicast Check: Open Simatic Shell on all virtualized OS servers and clients. Confirm that all nodes discover each other across the terminal bus vSwitch without requiring name resolution workarounds.
Plant Bus Communication and BCE Diagnostics: In Set PG/PC Interface, verify that PC internal.local.1 or the virtualized network adapter communicates via Softnet-IE to physical S7-400 CPUs. Verify connection state in HW Config.

Limitations and Operational Precautions

When deploying PCS 7 in a virtualized Dell VRTX chassis, observe the following operational constraints:

CP1623 / CP1628 Hardware Cards: Physical PCI communication processors (such as CP 1623) cannot be directly installed into blade servers without PCI passthrough. Siemens recommends using standard vNICs with Softnet-IE BCE licenses instead.
Time Synchronization Drift: Never allow VMware Tools to synchronize the guest operating system time with the ESXi host. Virtual machines must synchronize strictly via standard industrial NTP sources or the plant domain controller to prevent SQL Server timestamp inversion errors.
Commercial Procurement and Licensing Disclaimer: Virtualization does not reduce software license requirements. Every virtualized OS Server, Client, and Web Server requires standard runtime and option licenses via Automation License Manager. Validate exact MLFBs with an authorized Siemens sales representative.

Engineer FAQ

Can I run an Engineering Station (ES) inside a VMware virtual machine?

Yes. PCS 7 Engineering Stations are released for virtualized operation. However, USB hardware dongles or direct fieldbus connections require network license managers (ALM via TCP/IP) and Ethernet-based communication.

Is Dell PowerEdge VRTX explicitly certified by name in Siemens documentation?

Siemens does not certify specific PC hardware models; instead, Siemens certifies VMware vSphere ESXi versions. As long as Dell VRTX is certified on the VMware HCL for the supported ESXi version, it fulfills Siemens requirements.

Why is memory reservation mandatory for WinCC OS Server VMs?

WinCC OS Servers rely heavily on Microsoft SQL Server, which caches data in RAM. If the hypervisor dynamically reallocates or balloons memory to other VMs, SQL Server execution stalls, causing WinCC archive drops and runtime freezes.