Intermittent PLC connection loss in VM

[Dustball]

Hello all,

I have a system going through checkout that is running a FT server in a VM that is hosted on a PC. The PC host is running a FT View SE client. This system is a BTP that uses identical software from 8 previous builds in 2017/2018 so the software is known to be working.

What's happening is that the PLC connection will be lost at random times days or weeks apart.

Occurrences:
10/29 2:27 AM
11/27 1:53 AM
12/5 2:23 PM
12/10 1:24 PM

After reviewing the Windows Events and FT Diagnostics logs on the host PC and VM, I found one common denominator with the PLC connection loss errors. Whenever the PLC connection is lost, there is also a ~3 minute time jump in the VM’s Windows system clock.

I've attached pictures of the Windows Events log and FT Diagnostics log with filtering to show the system time changes and the PLC connection loss errors. Those highlighted dates were when the system time jumped three minutes. The other Windows events were minimal clock jumps of milliseconds as the VM is set to sync it’s clock with the host. The clock updates in the host occur once a week every Sunday at 1:00 AM (11/1, 11/15, 11/22, 11/29, 12/6) and the VM’s clock is updated at the same time.

The VM resumes the PLC connection within 20 seconds.

Does anyone know how the system time jumps can be related to the PLC connection losses or where I should be looking?

Windows 7 Pro SP1 64-bit on both the host and VM.
Studio 5000 v28.01
FT View SE and SE Client 8.20.00
FTSP 2.80.00
VMWare 11.1.4

Thanks,
Dustin

 

[Dustball]

New information after examining the VM logs.

This happens each time-
2020-11-27T01:36:01.966-08:00| vmx| I120: MemSched: Balloon enabled 1 guestType 4 maxSize 0
2020-11-27T01:53:01.708-08:00| vcpu-0| I120: sata0:0: Command *UNKNOWN (0x4a)* took 179.996 seconds (ok)
2020-11-27T01:53:01.713-08:00| vcpu-0| I120: AHCI-VMM: sata0:0 Port COMRESET requested.
2020-11-27T01:53:01.713-08:00| vcpu-0| I120: AHCI-VMM: sata0:0: Moved to COMRESET state.
2020-11-27T01:53:01.713-08:00| vcpu-0| I120: AHCI-VMM: sata0:0: Exiting COMRESET state.
2020-11-27T01:53:01.767-08:00| vcpu-0| I120: AHCI-SHARED:Not posting RFIS on port: 0, since FR bit is not set.


2020-12-05T14:02:59.703-08:00| vmx| I120: MemSched: Balloon enabled 1 guestType 4 maxSize 0
2020-12-05T14:23:11.040-08:00| vcpu-0| I120: sata0:0: Command *UNKNOWN (0x4a)* took 179.998 seconds (ok)
2020-12-05T14:23:11.043-08:00| vcpu-0| I120: AHCI-VMM: sata0:0 Port COMRESET requested.
2020-12-05T14:23:11.043-08:00| vcpu-0| I120: AHCI-VMM: sata0:0: Moved to COMRESET state.
2020-12-05T14:23:11.044-08:00| vcpu-0| I120: AHCI-VMM: sata0:0: Exiting COMRESET state.
2020-12-05T14:23:11.050-08:00| vcpu-0| I120: AHCI-SHARED:Not posting RFIS on port: 0, since FR bit is not set.



2020-12-10T13:07:54.327-08:00| vmx| I120: MemSched: Balloon enabled 1 guestType 4 maxSize 0
2020-12-10T13:24:03.554-08:00| vcpu-0| I120: sata0:0: Command *UNKNOWN (0x4a)* took 179.997 seconds (ok)
2020-12-10T13:24:03.558-08:00| vcpu-0| I120: AHCI-VMM: sata0:0 Port COMRESET requested.
2020-12-10T13:24:03.558-08:00| vcpu-0| I120: AHCI-VMM: sata0:0: Moved to COMRESET state.
2020-12-10T13:24:03.559-08:00| vcpu-0| I120: AHCI-VMM: sata0:0: Exiting COMRESET state.
2020-12-10T13:24:03.571-08:00| vmx| I120: AHCI-SHARED:Not posting RFIS on port: 0, since FR bit is not set.

sata0:0 is the CD/DVD ROM drive in the VM so I've just now disabled that and hopefully that fixes it.

Leaving this thread up in case someone else runs into intermittent communications issues in their VM.

Thanks,
Dustin