Troubleshooting

Learn how to troubleshoot connection issues with JRebel Debugger Proxy (JDP).

Issue: Cannot connect to JDP

  • Check firewall rules.

  • Check if JDP has started on the target host (from JRebel native agent).

  • Check whether the target process has written Proxy listening on port ... and will connect to localhost: ... to stdout.

  • Check <rebel base>/bootcache/jrebel.boot.log for lines similar to the following:

JRebel-JVMTI [DEBUG] Executing [/Users/myuser/.sdkman/candidates/java/21.0.6-tem/bin/java, -Drebel.base=./rebel_base, -Drebel.parent.pid=98819, -jar, /Users/myuser/IdeaProjects/SidecarTestbed/jrebel/jr-debugger-proxy.jar, 9199, localhost, 8188]
JRebel-JVMTI [DEBUG] Child PID: 98820

Issue: Cannot reconnect to JDP (after one or more successful connection attempts)

Kill the JDP process.

The JDP PID can be found as "Child PID: …" at the end of <rebel base>/bootcache/jrebel.boot.log.

JDP is restarted automatically by JRebel Agent in the target process.