Q:

Remote Debugging Fails with IntelliJ but works with Eclipse?

I'm attempting to debug a program running in WebSphere Liberty Profile, so I run this on the server:
./server debug

This prints out
Listening for transport dt_socket at address: 7777

In IntelliJ IDEA, version 13.1.3, I try:
Run > Edit Configurations > + > Remote.
I pick Socket, Attach, fill in the hostname, and enter the port number of 7777, give it a name, and then OK.
Run > Debug > Pick the name I just gave it.
It opens a debugger tab and after ~30 seconds it displays the message
Error running (debugger configuration name):
Unable to open debugger port:
java.net.ConnectException "Connection timed out: connect"

(Line breaks added to make it easier to read).
I can then launch Eclipse, Kepler Service Release 2, and do
Run > Debug Configurations... > Remote Java Application > New > give it a name, pick Socket Attach, give it the host name and port number of 7777, click Apply, and Debug.
And it works just fine.
The fact that I can run Eclipse and have it work fine and IntelliJ and have it fail at the same time indicates to me that the problem isn't anywhere on my server and it's not an issue with my network connection.
It seems to me that the problem must lie somewhere in how I've set up IntelliJ. So my question is: what could I have done right with Eclipse that I'm getting wrong with IntelliJ?

A:

The error message shows that IntelliJ IDEA can't establish a network connection to the debuggee process. One common reason for this problem is a local firewall rule that blocks network connections from IntelliJ IDEA.

