ROS2 multicast send and receive only works in one direction

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I have 2 Intel NUCs running Ubuntu 16.04 and ROS2 Crystal. On one machine I can run "ros2 multicast receive" and run "ros2 multicast send" on the other with success. However when I try and do it the other way around I am unsuccessful. Locally I see the message but it only makes it one way across the network.

I'm new to this so please let me know what additional information I can provide and how to do so