@Paul Thanks for reaching out. As mentioned by Anthony Public port scanning traffic could be hitting your ACA instance periodically and causing it to start up and shut down frequently. This is a common issue with publicly exposed services, and it can be difficult to prevent.
One way to mitigate this issue is to use a firewall or NSG to restrict access to the MongoDB server. You can configure the firewall or NSG to only allow traffic from specific IP addresses or ranges, which can help reduce the amount of port scanning traffic hitting your ACA instance.
Another option is to use a reverse proxy or load balancer to route traffic to the MongoDB server. This can help hide the server's IP address and make it more difficult for attackers to target it with port scanning traffic.
do let me know incase of further queries, I would be happy to assist you.
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