# Troubleshooting System Debugger

There are two primary components to review when troubleshooting System Debugger problems:

1. The DEBUG HUB handles incoming requests for starting debug servers, and serves as a registry for clients that want to use the graphical debugging capabilities of the System Debugger. Clients register with the debug hub from the debug manager window. When a client is registered, both the user information as well as the connection information of the client is stored in the registry.

   The properties of the debug hub are:

   - Server - DEBUG HUB
   - Server Job Name - QTESDBGHUB
   - Server Type - QIBM_DEBUG_SERVER
   - Server Description - Graphical Debug Server
   - Job User - QPGMR
   - Job Type - BATCH
   - Subsystem - QSYSWRK
   - Startup Command - STRTCPSVR *DBG

   Ensure that the DEBUG HUB is active on your system. If it is not active, enter the command STRTCPSVR *DBG to start the server.

2. The TCP/IP server DEBUG SERVER starts upon a request from the DEBUG hub. The debug server creates debug server jobs that connect to the registered client and services the jobs specified in the Start Debug dialog.

   The properties of the debug server are:

   - Server - DEBUG SERVER
   - Server Job Name - QTESDBGSVR
   - Server Type - QIBM_DEBUG_SERVER
   - Server Description - Graphical Debug Server
   - Job User - Authenticated user performing debug
   - Job Type - BATCH
   - Subsystem - QUSRWRK

   Ensure that the DEBUG SERVER job is active on your system. If it is not active and the DEBUG HUB is active on your system, check the QTESDBGSVR job log for additional information. All instances of the QTESDBGSVR job are submitted to the QUSRNOMAX job queue, which feeds the QUSRWRK subsystem. To ensure that the debug server runs properly, make sure that the QUSRNOMAX job queue is not held and that the QUSRWRK subsystem is currently running.