Unable to open debugger port in IntelliJ

Question

Unable to open debugger port in intellij. The port number 9009 matches the one which has been set in the configuration file for the application.

Answer 1

This error can happen Tomcat is already running. So make sure Tomcat isn't running in the background if you've asked Intellij to start it up ( default ).

Also, check the full output window for more errors. As a more useful error may have preceded this one ( as was the case with my configuration just now )

Answer 2

I once have this problem too. My solution is to work around this problem by kill the application which is using the port. Here is a article to teach us how to check which application is using which port, find it and kill/close it.

Answer 3

You may have to change the debugger port if your port is already used by another program. To do so:

• Run
• Edit Configurations
• Startup/Connection tab
• Debug
• Change the port here

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Or, maybe in other versions:

• Run
• Edit Configurations
• Remote > Remote debug in the list on the left
• Configuration tab, Settings section
• Port: change the port here

Answer 4

I had the same problem and this solution also did the trick for me: Provide the IP 127.0.0.1 in the Intellij Debug configuration instead of the host name "localhost", in case you're using this hostname.

Answer 5

You must set CHMOD +x (execute for *.sh or *.bat files). For example, I am using macOS

cd /Users/donhuvy/Documents/tools/apache-tomcat-9.0.12/bin
sudo chmod +x *.sh

Then IntelliJ IDEA, and Apache Tomcat running or debugging just good.