Drew Bliss from Microsoft posted a note on NTDEV today, in response to a question about debugging and CLR, and in the process pointed out a really interesting utility that ships with the new debugging packages called kdbgctrl. I decided to look into it.
It only works on 3790 and better, meaning Windows Server 2003 and Windows XP x64 Edition, and Vista of course. Here’s the output from a Vista box (identical to my x64 box):
C:\Program Files\Debugging Tools for Windows 64-bit>kdbgctrl
Usage: kdbgctrl
Options:
-c - Check kernel debugger block-enable
-ca - Check kernel debugger auto-enable
-cb - Check kernel debugger enable block
-cdb - Check kernel DbgPrint buffer size
-cu - Check kernel debugger user exception handling
-cx - Check kernel debugger enable and exit with status
-d - Disable kernel debugger
-da - Disable kernel debugger auto-enable
-db - Disable kernel debugger block-enable
-du - Disable kernel debugger user exception handling
-e - Enable kernel debugger
-ea - Enable kernel debugger auto-enable
-eb - Enable kernel debugger block-enable
-eu - Enable kernel debugger user exception handling
-sdb - Set kernel DbgPrint buffer size
-td - Get a kernel triage dump
C:\Program Files\Debugging Tools for Windows 64-bit>kdbgctrl.exe -c
Kernel debugger is enabled
C:\Program Files\Debugging Tools for Windows 64-bit>kdbgctrl.exe -ca
Kernel debugger auto-enable: false
C:\Program Files\Debugging Tools For Windows 64-bit>kdbgctrl.exe -cb
Kernel debugger enable block: false
C:\Program Files\Debugging Tools for Windows 64-bit>kdbgctrl.exe -cdb
Kernel DbgPrint buffer size: 0x1000
C:\Program Files\Debugging Tools for Windows 64-bit>kdbgctrl.exe -cu
Kernel debugger user exception enable: true
That last option, -cx, looks useful for scripting. Other than this, documentation is very light on this tool. It was mentioned a few times in the newsgroups and on the mailing lists, but not much else.
How to enable a remote kernel debugger connection on a computer that is running Windows Server 2003 with Service Pack 1 has some more information.