Hitting an interesting issue that I hope others have seen. Following the steps here: https://github.com/Automattic/cm-livy-scripts, we've created a parcel for Livy and added the service to our existing CDH cluster - colocating it with services on an existing master node. We've noticed that whenever Livy is running, network access to the node it was started on is blocked - all ports, ICMP requests still go through. When we stop Livy, we can once again ssh to the node and connect to ports of other running services. Firewalld isn't running on any cluster nodes. We rely on security groups. Any ideas why/how Livy would be doing this?