I have a java application running on an openshift remote cluster and I want to debug the app from my local machine with Intellij-Idea. The app is built by a Jenkinsfile on another remote jenkins server (gradle build, docker build and pushed to openshift, where it is automatically deployed).
The Dockerfile exposes port 9009 and therefore my Intellij Remote Debug Config looks like this:
Debug Config
With the localhost in the Debug Config I need openshift port-forwarding:
oc port-forward my-pod 9009
Forwarding from 127.0.0.1:9009 -> 9009
When I start the Debugger I get the following error in Intellij:
Error running 'DTC Remote Debug':
Unable to open debugger port (localhost:9009): java.net.ConnectException "Connection refused: connect"
At the same time the terminal with the port forwarding shows:
Handling connection for 9009
E0927 09:52:33.711817 5996 portforward.go:331] an error occurred forwarding 9009 -> 9009: error forwarding port 9009 to pod ad370...c010, uid : exit status 1: 2019/09/27 03:52:33 socat[129691] E connect(5, AF=2 127.0.0.1:9009, 16): Connection refused
Doing an Nmap scan against the url where I get the index.html of my application I got the following:
nmap -sS my-openshift-url
Starting Nmap 7.80 ( https://nmap.org ) at 2019-09-27 15:01 Mitteleuropõische Sommerzeit
Nmap scan report for my-openshift-url (IP-Address)
Host is up (0.0043s latency).
rDNS record for IP-Address: dispatch-my-domain
Not shown: 997 filtered ports
PORT STATE SERVICE
80/tcp open http
443/tcp open https
9009/tcp closed pichat
Nmap done: 1 IP address (1 host up) scanned in 6.10 seconds
I guess the problem is the closed 9009 port, but I have no clue how I can open that port on my openshift cluster. I already set several environment variables in the openshift web UI (just to be sure):
DEBUG TRUE
DEBUG true
DEBUGGING TRUE
DEBUGGING true
JAVA_DEBUG TRUE
JAVA_DEBUG true
JAVA_DEBUG_PORT 9009
But I can't get it to work. If I switch the port-forwarding to 8080 I can access the index.html via localhost:8080 from my browser. I don't know if I need to change something in the project code (gradle, docker, jenkins, etc.) or if I can just open the port on the deployed service in openshift somehow...
If anything isn't clear or if I missed something just tell me. I'm happy for every piece of advice.
Regards,
Christoph
Adding the following environment variable in openshift did the trick:
JAVA_TOOL_OPTIONS -agentlib:jdwp=transport=dt_socket,address=9009,server=y,suspend=n
All the other environment variables from above are absolete...
I am trying to debug a simple Java application on my machine using Eclipse as an IDE. When I try to debug the application by entering the Debug Perspective, I set a breakpoint and start debug. Within a few seconds, the following pop-up window:
Launching unicodeRead has encountered a problem. Cannot connect to VM.
The message dumped on the console is as follows:
ERROR: transport error 202: connect failed: Connection refused
ERROR: JDWP Transport dt_socket failed to initialize, TRANSPORT_INIT(510)
JDWP exit error AGENT_ERROR_TRANSPORT_INIT(197): No transports initialized [../../../src/share/back/debugInit.c:708]
FATAL ERROR in native method: JDWP No transports initialized, jvmtiError=AGENT_ERROR_TRANSPORT_INIT(197)
How do I correct this? Why does this happen?
I just had the same problem.
Yesterday everything worked fine, now nothing - same error as you gave. I found out that network admins made some changes in the meantime. Some firewall stuff. Problem is that Eclipse tries to establish connection to JVM at "localhost" (and some random port). When I tried pinging localhost (or 127.0.0.1) I got following:
C:\Windows\system32>ping 127.0.0.1
Pinging 127.0.0.1 with 32 bytes of data:
PING: transmit failed. General failure.
PING: transmit failed. General failure.
PING: transmit failed. General failure.
PING: transmit failed. General failure.
and
C:\Windows\system32>ping localhost
Ping request could not find host localhost. Please check the name and try again.
It seams that in some cases DNS is expected to resolve this, and if firewall prevents localhost requests to DNS - stuff breaks. I had to alter hosts file and remove comments in following lines, so I would not rely on DNS for this anymore:
# 127.0.0.1 localhost
# ::1 localhost
Although it is written that hosts file changes take effect immediately, I think that some processes locked this and restart was necessary in my case. After that, everything worked again.
Had same problem, but the solution was to run the application with -server=y option and not with -server=n.
Before:
java -agentlib:jdwp=transport=dt_socket,server=n,suspend=y,address=localhost:5005
After:
java -agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=localhost:5005
Looks like the same problem as here. A reboot of the pc fixed the problem there. I haven't found any other solutions.
I was seeing an error while using the -X format:
java -Xdebug -Xrunjdwp:server=y,transport=dt_socket,address=4000,suspend=n myapp
The error went away when I switched to the newer format:
java -agentlib:jdwp=transport=dt_socket,server=y,address=4000,suspend=n myapp
Its Very Simple,Just do the Following Changes in eclipse.ini file.
-vm
binary\com.sun.java.jdk.win32.x86_1.6.0.u43\jre\bin\javaw.exe
I changed
-agentlib:jdwp=transport=dt_socket,address=9009,server=n,suspend=y
to
-agentlib:jdwp=transport=dt_socket,address=9009,server=y,suspend=n
and that did the trick!
My case is I have a bunch of domains refer to 127.0.0.1 in hosts file, like this:
127.0.0.1 localhost domian1.local domain2.local domain3.local
one day I added another new domain to refer to 127.0.0.1. By mistake, I put the domain in front of "localhost", like this:
127.0.0.1 domain4.local localhost domian1.local domain2.local domainx.local
After this, I always got an alert window in eclipse while debugging:
Cannot connect to VM
com.sun.jdi.connect.TransportTimeoutException
In console:
ERROR: transport error 202: connect failed: Connection refused
ERROR: JDWP: Failed to initialize transport via localhost:50470, trying localhost via 127.0.0.1:50470
FATAL ERROR in native method: JDWP No transports initialized, jvmtiError=AGENT_ERROR_TRANSPORT_INIT(197)
ERROR: transport error 202: connect failed: Connection refused
ERROR: JDWP Transport dt_socket failed to initialize, TRANSPORT_INIT(510)
JDWP exit error AGENT_ERROR_TRANSPORT_INIT(197): No transports initialized [../../../src/share/back/debugInit.c:690]
The solution is keep "localhost" at the first position all the time.
127.0.0.1 localhost domian1.local domain2.local domainx.local domain4.local
What solved for me was deleting the entire domain1 folder inside the domains folder on glassfish main folder.
Eclipse will ask you to recreate a domain and then everything works again.
In eclipse select Run tab -> Debug configuration -> Junit -> select your test name ->
Environment tab -> add variable server=y .
I was getting the same error on my ubuntu machine because of a mishap with the /etc/hosts file. I had commented out the mapping of localhost to 127.0.0.1, and to complicate matters further there was a swap file hanging around.
This was the first line of my /etc/hosts:
127.0.0.1 #localhost
Deleting the # fixed the problem, whereas rebooting understandably had not.
My cause & solution were completely different.
I think in my case it was due to the installation of JProfiler. I fixed it by uninstalling JProfiler and launching eclipse with the -clean option. I suspect that JProfiler was inserting itself in the debugger. The -clean option forces Eclipse to re-assess its plugins, so that alone might have been sufficient.
Continuing #gonadarian's answer, it seems Eclipse uses port 127.0.0.1 for debug purposes. This port is also called localhost. The way this error can be removed is by ensuring that there are no processes or services running on the above ports. The way to do this, on Linux is:
As root, enter the command:
netstat -tulpn | grep 127.0.0.1
If there are processes running on the above port, it will show up in the format:
process_id/process name.
Kill the above processes like so: kill -KILL process_id
Restart the computer for these changes to take effect. The error should no longer occur.
I'm trying to attach my Eclipse debugger running on my Windows host to a Tomcat 8 server running in my Vagrant box running CentOS 7.
The issue is something to do with the networking setup of Vagrant I believe.
Here is the full error from the Eclipse logs:
java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:179)
at java.io.DataInputStream.readFully(DataInputStream.java:189)
at java.io.DataInputStream.readFully(DataInputStream.java:163)
at org.eclipse.jdi.internal.connect.SocketTransportService.readHandshake(SocketTransportService.java:216)
at org.eclipse.jdi.internal.connect.SocketTransportService.access$7(SocketTransportService.java:212)
at org.eclipse.jdi.internal.connect.SocketTransportService$3.run(SocketTransportService.java:183)
at java.lang.Thread.run(Thread.java:761)
The output from vagrant up seems correct (port 8000 is the debugging port):
==> default: Preparing network interfaces based on configuration...
default: Adapter 1: nat
==> default: Forwarding ports...
default: 8000 => 8000 (adapter 1)
default: 8443 => 8443 (adapter 1)
default: 22 => 2222 (adapter 1)
I can access my application (using https://localhost:8443/app) via a browser from my host without issue; connecting the debugger is the issue. The debugger is configured for a Remote Java Application with connection properties:
Host: localhost
Port: 8000
Starting Tomcat of course displays the correct:
Listening for transport dt_socket at address: 8000
Based on the following questions, the answer maybe have something to do with configuring Tomcat to run on 0.0.0.0 instead of the default:
Cannot reach Jekyll server on Vagrant from outside
Vagrant port forwarding not working. Cups not accesible from host
Empty reply from server - can't connect to vagrant vm w/port forwarding
Connection Reset when port forwarding with Vagrant
So I tried configuring the Connectors in Tomcat's server.xml with the line address="0.0.0.0" but the result was the same.
Any other ideas about getting this to work? Also, assuming the answer is something to do with changing the address to 0.0.0.0, why would I need to do that to get the debugger to work if accessing the app via browser is already fine on localhost:8443?
P.S. It is not a firewall issue.
I was on the right track above changing the address to 0.0.0.0, but I was changing that on the Connector in server.xml, which has nothing to do with the debugger. The resolution is to change the JPDA_ADDRESS resulting in my bin/setenv.sh getting:
JPDA_ADDRESS="0.0.0.0:8000"
This is due to a change in Tomcat 8:
When starting Tomcat with the jpda option to enable remote debugging,
Tomcat 8 listens on localhost:8000 by default. Earlier versions
listened on *:8000. If required, this default can be overridden by
setting the JPDA_ADDRESS environment variable in, for example,
setenv.[bat|sh].
i'm using Glassfish 3.1.2.2 and Eclipse Kepler.
Glassfish configuration:
-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=9009.
Debug: Enabled
Into Eclipse, in the Remote Java Application i've selected the project, and in the connection properties i've set:
Host: localhost
port: 9009
When i try to connect the debug, the message error is:
Failed to connect to remote VM. Connection refused.
Connection refused: connect
I've checked the port 9009 with a telnet, and is not used...
can someone help me?
tx
[SOLVED] it's a problem with the glassfish plugin in Eclipse! you must to start glassfish form the command line, not from the Eclipse window. After, you can connect like remote debug to your local glassfish ;)
In Host, you need to give IP address of the remote machine you want to connect.
localhost is your own machine.
I setup my remote WebLogic server to debug, using these options:
-Xdebug -Xnoagent -Xrunjdwp:transport=dt_socket,address=${DEBUG_PORT},server=y,suspend=n -Djava.compiler=NONE"
I started WebLogic on the server and saw that it was listening on 8453 for dt_socket. I added the remote server on my local Eclipse and tested the connection. I also see that the server is STARTED and I can view the details. However, I'm unable to restart in DEBUG. I also stopped WebLogic on the server and now in Eclipse I see that it is stopped, but I'm not able to start it (the icons for debug and start are greyed out). When I set up my Remote Java Application in Eclipse I did check "Allow termination of remote VM".
Before stopping the server, the debug icon wasn't disabled and when I clicked it I got this message:
Cannot attach to remote server.
Please make sure the server myserver.com is running and listening for transport dt_socket at address: 8453
Failed to connect to remote VM. Connection refused.
Connection refused: connect
Instead of using java startup options, modify the following scripts:
setDomainEnv.sh -> make sure DEBUG_PORT is set ie. 8453
startWebLogic.sh -> set PRODUCTION_MODE=false and set debugFlag=true
Restart server, remote debug should work on port 8453.