In JDK-8004213, JDK 8, the field RMI_HOSTNAME was added to the JDP packet, value comes from the property java.rmi.server.hostname.
The hostname value does not make it's way into the the jmx service url, which is the only thing JMC uses to connect.

The service url when I start a local JVM with JDP enabled on my machine is:
service:jmx:rmi:///jndi/rmi://klara02:4712/jmxrmi
If someone else sees this connection, they can't use it because they can't necessarily resolve what 'klara02' is, and even if I override java.rmi.server.hostname it does not help.

Workaround on the server side is to specify -Dcom.sun.management.jmxremote.host (since 8u102)

Not sure if this would be considered a JDK bug or not, have not opened one yet.