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NAME="SETUP"
>4. Setup, Test, and Running crash</A
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><A
NAME="AEN87"
>4.1. Setting up crash dump</A
></H2
><P
> In order to save a core image that has been written into swap,
the image must be saved prior to swap being re-mounted during
boot. To accomplish this, the <TT
CLASS="FILENAME"
>sysinit</TT
>
startup file needs to be changed. The lkcd source includes a
<TT
CLASS="FILENAME"
>scripts</TT
> directory which contains patches
for various sysinit startup scripts. These patches add the
<B
CLASS="COMMAND"
>lkcd config</B
> and <B
CLASS="COMMAND"
>lkcd save</B
>
commands to enable crash dumps and to save any existing crash
dumps upon startup. </P
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><A
NAME="AEN94"
>4.2. Testing crash</A
></H2
><P
> To force a panic to test you new crash setup, compile the following
code with <B
CLASS="COMMAND"
>cc -c -I/usr/src/linux/include panic.c</B
> .
After building the <TT
CLASS="FILENAME"
>panic.o</TT
> module just
<B
CLASS="COMMAND"
>insmod panic.o</B
> to panic the kernel. </P
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> ### panic.c ###########################
#define __KERNEL__
# MODULE
# include init_module(void)
int init_module (void)
{
panic(" panic has been called");
return 0;
}
</PRE
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><A
NAME="AEN101"
>4.3. Running crash</A
></H2
><P
> To view your kernel core file <B
CLASS="COMMAND"
>lcrash</B
> needs
to be invoked with a couple of parameters: </P
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> <B
CLASS="COMMAND"
>lcrash [ System.map file ] [ dump image ] [ Kerntypes ]</B
>
Example:
<B
CLASS="COMMAND"
>lcrash /boot/System.map ./dump.1 /boot/Kerntypes</B
>
</PRE
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><P
>It will take a minute to load the kernel image into memory and drop
you into the crash shell. At the crash shell prompt you can type a
<TT
CLASS="USERINPUT"
><B
>?</B
></TT
> to see the available commands. </P
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