Data aggregator or data collector hang and the polling stops. The only way to start polling is restart of data aggregator or data collector.
Resource starvation during high usage by the other VM servers in a shared VM resources environment.
Reconfigure the Virtual Machine to have access to the necessary resources. The minimum memory settings should be at least the DA or DC memory allocation plus ActiveMQ allocation plus operating system requirements (2GB). Either set to Unlimited like the image below, or set Limit greater than the necessary memory
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