System Administration Guide: Basic Administration

ProcedureSPARC: How to Boot the System With the Kernel Debugger (kmdb)

This procedure shows you the basics for loading the kernel debugger (kmdb). For more detailed information, see the Solaris Modular Debugger Guide.


Note –

Use the reboot and halt command with the -d option if you do not have time to debug the system interactively. To run the halt command with the -d option requires a manual reboot of the system afterwards. Whereas, if you use the reboot command, the system boots automatically. See the reboot(1M) for more information.


  1. Halt the system, causing it to display the ok prompt.

    To halt the system gracefully, use the /usr/sbin/halt command.

  2. Type either boot kmdb or boot -k to request the loading of the kernel debugger. Press return.

  3. Enter the kernel debugger.

    The method used to enter the debugger is dependent upon the type of console that is used to access the system:

    • If a locally attached keyboard is being used, press Stop-A or L1–A, depending upon the type of keyboard.

    • If a serial console is being used, send a break by using the method that is appropriate for the type of serial console that is being used.

    A welcome message is displayed when you enter the kernel debugger for the first time.


    Rebooting with command: kadb
    Boot device: /iommu/sbus/espdma@4,800000/esp@4,8800000/sd@3,0
    .
    .
    .

Example 13–5 SPARC: Booting a System With the Kernel Debugger (kmdb)


ok boot kmdb
Resetting...

Executing last command: boot kmdb -d
Boot device: /pci@1f,0/ide@d/disk@0,0:a File and args: kmdb -d
Loading kmdb...