JAVA_HOME not set for Debug Service

[zkarj735]

Having just updated an LPAR with the required PTFs for Debug Server 3.0, I can successfully start the Debug Server, but the Debug Service fails to start.

Checking the joblog, I see the start command is this:

QSH CMD('export JAVA_HOME=undefined;/QIBM/ProdData/IBMiDebugService/bin/startDebugService.sh > /QIBM/UserData/IBMiDebugService/startDebugService_workspace/startDebugServiceNavigator.log 2>&1')

Perhaps unsurprisingly, this fails with an error (from the log file).

Environment variable JAVA_HOME is not set or is set faulty.
JAVA_HOME=undefined

Where is it getting the value for JAVA_HOME from?

---

⚠️ REMOVE THIS LINE AND ANY SENSITIVE INFORMATION BELOW! ⚠️

Context	Version
Code for IBM i version	2.16.3
Visual Studio Code version	1.97.2
Operating System	win32_x64

Active extensions

Code for IBM i Walkthroughs (vscode-ibmi-walkthroughs): 0.5.0
Configuration Editing (configuration-editing): 1.0.0
Db2 for IBM i (vscode-db2i): 1.13.3
Emmet (emmet): 1.0.0
Error Lens (errorlens): 3.26.0
Git (git): 1.0.0
Git Base (git-base): 1.0.0
GitHub (github): 0.0.1
GitHub Authentication (github-authentication): 0.0.2
GitLens — Git supercharged (gitlens): 17.3.3
IBM i Debug (ibmidebug): 3.0.0
IBM i Project Explorer (vscode-ibmi-projectexplorer): 2.12.3
JSON Language Features (json-language-features): 1.0.0
Merge Conflict (merge-conflict): 1.0.0
Node Debug Auto-attach (debug-auto-launch): 1.0.0
Server Ready Action (debug-server-ready): 1.0.0
Source Orbit (vscode-sourceorbit): 1.4.1
Todo Tree (todo-tree): 0.0.226
TypeScript and JavaScript Language Features (typescript-language-features): 1.0.0

---

Remote system

Setting	Value
IBM i OS	V7R4M0
Tech Refresh	11
CCSID Origin	65535
Runtime CCSID	65535
Default CCSID	37
SSHD CCSID	?
cqsh	true
SQL	Enabled
Source dates	Disabled

Enabled features

/QOpenSys/pkgs/bin	/usr/bin	/QSYS.lib/ILEDITOR.lib	/QSYS.LIB	/QIBM/ProdData/IBMiDebugService/bin	/QOpenSys/QIBM/ProdData/JavaVM/jdk80	/QOpenSys/QIBM/ProdData/JavaVM/jdk17
bash	attr	GETNEWLIBL.PGM	QZDFMDB2.PGM	startDebugService.sh	64bit	64bit
chsh	iconv
find	setccsid
git	uname
grep
ls
md5sum
sort
stat
tar
tn5250

Shell env

BUILDLIB=QGPL
CURLIB=QGPL
HOME=/home/T816416
HOST=ia1367.telecom.co.nz
JAVA_HOME=/QOpenSys/QIBM/ProdData/JavaVM/jdk17
LIBLS=QTEMP QGPL ICMSSW
LOGIN=t816416
LOGNAME=t816416
MAIL=/var/spool/mail/t816416
OLDPWD=/home/T816416
PASE_USRGRP_LIMITED=N
PATH=/QOpenSys/pkgs/bin:/QOpenSys/usr/bin:/usr/ccs/bin:/QOpenSys/usr/bin/X11:/usr/sbin:.:/usr/bin:/QOpenSys/usr/bin:/usr/bin
PWD=/home/T816416
SHELL=/QOpenSys/pkgs/bin/bash
SHLVL=1
SSH_CLIENT=10.236.163.2 55971 22
SSH_CONNECTION=10.236.163.2 55971 146.171.64.181 22
TZ=<NZST>-12<NZDT>,M9.5.0,M4.1.0/03:00:00
USER=t816416
USERNAME=t816416
WORKDIR=/home/T816416
_=/QOpenSys/pkgs/bin/env

Variants

{
  "american": "#@$",
  "local": "#@$"
}

[chrjorgensen]

@zkarj735 Can you start the Debug Service in Navigator for i? Starting the service has been moved to the server side and will eventually be removed from Code for IBM i.

If you have problems starting the service in Navigator, please check your group PTF level for HTTP:
SF99662 - 740 IBM HTTP Server for i, level 45, released 2025-06-27.

[zkarj735]

Thanks. The PTF level is correct. I remembered seeing the stuff about Navigator in the docs so revisited those, including regenerating the certificate.

On attempting to start the Debug Service, I saw a very quick flash of messages at the top of the screen but otherwise no feedback. Checking on server jobs, I saw only QB5ROUTER running under my profile.

I then noticed Start Instance > System Debugger was available (despite VSCode showing the Server was running). I chose that, then chose to start Debug Service again. Once more no feedback. VSCode says the Service is not running, but Navigator now shows QB5ROUTER and QTESDBGHUB under QPGMR.

Start Instance > Debug Service remains available on the menu, indicating it is not running.

[zkarj735]

We have the 3.0.0 debugger working now. The chief issue was we had Java 8 and 17 but not 11. I've called out a documentation improvement in this regard here: #2835

It's worth noting when starting the Debug Service from Navigator, that the menu option does not grey out once it is started. This was acknowledged by IBM as a bug. We have gone with starting the Server and Service from the 5250 command line (in fact, QSTRUP), using STRDBGSVR and the command specified here: #2720

[zkarj735]

It is probably worth tweaking the JAVA_HOME processing so it does something more meaningful than just saying it is invalid. Especially given the invalidity is generated by the plugin itself.

[chrjorgensen]

Just for clarification, the Debug Service is a separate extension and server component maintained by IBM and cannot be changed by the Code for IBM i developers. But keep reporting issues with the Debug Service, IBM is monitoring for debug issues here and will take appropriate action.

[duieolson]

I will add a new piece of info to this thread.

I was having exactly the same problem as Allister based on the initial post. I couldn't get the service to start.
I had the PTF for v7r5.
I had the Java 11.
I had the cert generated and ready.
The service would NOT start. Nothing indicating why. I put a jobd with full logging on and tried to restart the service in VSCode. Of course failed, but now with the joblog I could see the same QSH command being executed that Allister posted.
When I looked at that defined output log, it contained a line about not able to write to /QIBM/UserData/IBMiDebugService/configuration/QDBGSRV
I looked in my IFS and I didn't even have a configuration directory in my /QIBM/UserData/IBMiDebugService.
So I built the configuration/QDBGSRV structure within the /QIBM/UserData/IBMiDebugService/ directory and changed ownership to QSYS on both.
The last piece I needed was to grant the QDBGSRV profile to have write permissions in the QDBGSRV directory so it can write the configuration files to the directory.
They the service started for me.

Hope this helps in troubleshooting for others.