How to Force a Crash Dump When the Solaris Operating System is Hung

How to Force a Crash Dump When the Solaris Operating System is Hung.

This post describes steps for forcing a system crash dump when the Solaris system is in a hang condition. First of all, you need to drop the system into OK Prompt. For Old model which has Sun keyboard, you can press STOP+A, or for newer model / terminal, press break key sequences, example:

If your console is a terminal, you can type :
“shift-break”    or
“ctrl-break”    or
“ctrl-\” (ctrl-backslash) or
“<enter>” followed by “~” and
“ctrl-break”     on Solaris Sparc,

To send a <BREAK> from Hyperterm, use <Ctrl>-<Pause> or <Alt>-<Pause>
On Hyperterminal, Ctrl-Break

Okay after you able to drop system to the OK prompt, you will see below PROMPT messages:

Type ‘go’ to resume

All you need to do is to type ‘sync’ (without the quotes) and press Enter. The system will immediately panic. Now the hang condition has been converted into a panic, so an image of memory can be collected for later analysis. The system will attempt to reboot after the dump is complete.


Ref# Doc ID: 1004506.1


4 responses to “How to Force a Crash Dump When the Solaris Operating System is Hung

  1. Yes Aziz those key sequences only seem to be documented in dark hiidden corners of the web.
    The following may help someone out there on www. I found this after extensive searches on google so apologies to anyone I’ve ripped off.

    If you can break out to XSCF you can panic the OS with sendbreak. This may be useful.

    XSCF – Using sendbreak command in XSCF

    An M3000 “hung” at user login. Nil response to the power button and I was on the point of pulling the power, not the best option with lvm mirroring configured!
    No sun keyboard was connected so no “stop-a” keys available to initiate a panic to interrupt the O.S..
    In XSCF there is a “sendbreak” command but what I didn’t know was that by default sendbreak is disabled until “secure-mode” is set to off. If this is attempted with “secure-mode=on”, nothing happens when sendbreak is attempted:

    XSCF>sendbreak -d 0
    Send break signal to DomainID 0?[y|n] :y

    And nil response.

    So to change secure-mode, first check the current settings:

    XSCF> showdomainmode -d 0
    Host-ID :85021570
    Diagnostic Level :min
    Secure Mode :on
    Autoboot :on
    CPU Mode :auto

    So secure-mode is on so the OS won’t respond to sendbreak. To set secure-mode to off:

    XSCF> setdomainmode -d 0 -m secure=off
    Diagnostic Level :min -> –
    Secure Mode :on -> off
    Autoboot :on -> –
    CPU Mode :auto -> –
    The specified modes will be changed.
    Continue? [y|n] :y
    Diagnostic Level :min
    Secure Mode :off (host watchdog: unavailable Break-signal:receive)
    Autoboot :on (autoboot:on)
    CPU Mode :auto

    “sendbreak” now works.

    Consider setting secure-mode back to on when the crisis has been resolved 🙂

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