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====== Debugging Windows iSCSI boot ====== To debug Windows iSCSI boot problems, you will need a second Windows machine running //windbg//, and a null-modem cable to connect the two machines together via their serial ports. The debugging machine does not need to be running the same version of Windows as the iSCSI-booting machine. ===== Preparing the machines ===== Connect the null-modem cable between the serial port of the debugging machine and the serial port of the iSCSI-booting machine. (If one or both of the machines do not have serial ports then you can use a FireWire cable instead, but these instructions assume that you are using a null-modem cable.) ===== Preparing the tools ===== Download the latest version of //windbg// as part of the Debugging Tools for Windows package from [[http://www.microsoft.com/whdc/devtools/debugging/installx86.mspx]] and install it onto the debugging machine. Locate the Microsoft iSCSI initiator (which you have already downloaded and installed on the iSCSI-booting machine), and install it onto the debugging machine. ===== Preparing the iSCSI-booting machine ===== On the debugging machine, start the Microsoft iSCSI Initiator utility (//Start// -> //All Programs// -> //Microsoft iSCSI Initiator// -> //Microsoft iSCSI Initiator//). Go to the //Discovery// tab and click on //Add// to add a new target portal. Enter the IP address or DNS name of your iSCSI target. {{ :screenshots:windbg_iscsi_add_target.png?400x300 |Adding an iSCSI target}} Go to the //Targets// tab. You should see a list of available iSCSI target IQNs. Select the one containing your iSCSI-bootable Windows disk, and click on //Log On// to connect to the target. {{ :screenshots:windbg_iscsi_connect_target.png?400x300 |Connecting to the iSCSI target}} The iSCSI-bootable Windows disk should now show up as an extra drive in //My Computer// on the debugging machine. Start up //Notepad// and open the file //X:\boot.ini// (where //X:// is the drive letter for the iSCSI-bootable Windows disk). You should see something like [boot loader] timeout=30 default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS [operating systems] multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003" /fastdetect Duplicate the ''multi(0)disk(0)rdisk(0)partition(1)...'' line, and append the options /debug /debugport=com1 /baudrate=115200 /break (where //com1// is the serial port on the iSCSI-booting machine). The resulting file should look something like [boot loader] timeout=30 default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS [operating systems] multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003" /fastdetect multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003" /fastdetect /debug /debugport=com1 /baudrate=115200 /break Save this modified //boot.ini// file and close //Notepad//. Go back to the Microsoft iSCSI Initiator utility. On the //Targets// tab, select the one containing your iSCSI-bootable Windows disk, and click on //Details//. Tick the box next to the session identifier (which will be a long hex string such as //ffffffff810ca00c-4000013700000001//), and click on //Log off// to disconnect from the target. {{ :screenshots:windbg_iscsi_disconnect_target.png?400x300 |Disconnecting from the iSCSI target}} ===== Starting the debugger ===== {{ :screenshots:windbg_select_debug.png?360x200|Windows boot menu}} On the debugging machine, start the Windows debugger (//Start// -> //All Programs// -> //Debugging Tools for Windows// -> //WinDbg//). Start a kernel debugging session (//File// -> //Kernel Debug//). You should see the message "Waiting to reconnect...". Switch on the iSCSI-booting machine. You should reach the Windows boot menu offering you a choice such as Windows Server 2003 Windows Server 2003 [debugger enabled] Select the option including ''[debugger enabled]'' and press Enter to continue. You should see the screen go black, and the machine will appear to have frozen. This is because it is waiting for input from the debugger. ===== Using the debugger =====
