Schneider and I believe Allen bradley PLCs use vxworks. I have had a spate of trouble with Schneider quantum PLCs that would stop communicating when some Ethern

Schneider and I believe Allen bradley PLCs use vxworks. I have had a spate of trouble with Schneider quantum PLCs that would stop communicating when some Ethernet switches were upgraded. The program was still running and physical IO operating normally but no visibility in to the process and any Ethernet IO not working. definitely a weak point.