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kdump-config(8) | Linux System Administrator's Manual | kdump-config(8) |
NAME¶
kdump-config - configure kdump, check status, or save a vmcore fileSYNOPSIS¶
kdump-config { help | test | show | status | load | unload |
savecore }
DESCRIPTION¶
kdump-config manages the kdump feature of the Linux kernel. When a kdump enabled kernel panics, it immediately boots into a clean kernel called the kdump kernel. The memory image of the panicked kernel will be presented in /proc/vmcore while the kdump kernel (or "capture kernel") is running. kdump-config loads the kdump kernel into the current kernel and after a kdump, captures the vmcore image via kdump kernel. kdump-config can take advantage of the linux-image-$(uname -r)-dbg package and will try to use makedumpfile to capture the vmcore. The crash tool can then be used to analyze the vmcore at a later time. kdump-config exits with 0 on success and 1 on failure.COMMANDS¶
- help
- Print a usage summary.
- test
- Determine the parameters that would be used to load the kdump kernel, but do not load the kdump kernel. Useful for evaluating your configuration settings.
- show
- Show current parameters and the saved kexec command from the last kdump-config load.
- status
- Evaluate /sys/kernel/kexec_crash_loaded
and print a corresponding message.
- load
- Load the kdump kernel.
- unload
- Unload the kdump kernel.
- savecore
- If /proc/vmcore exists, save it using makedumpfile.
FILES¶
- /etc/init.d/kdump-tools
- init script to automatically load a kdump kernel, or save a vmcore and reboot.
- /etc/default/kdump-tools
- configuration file
- /var/crash/kernel_link
- a link to the current debug kernel
- /var/crash/kexec_cmd
- the last kexec_cmd executed by kdump-config
DIAGNOSTICS¶
- USE_KDUMP is not set or zero
- The variable USE_KDUMP in the file /etc/default/kdump-tools
is 0. To use kdump, edit the file and change the value to 1.
- kdump is not supported by this kernel
- The file /sys/kernel/kexec_crash_loaded does not exist. This means that the currently running kernel either was not configured to support kdump, or that a crashkernel= commandline parameter was not used when the currently running kernel booted.
- no crashkernel= parameter in the kernel cmdline
- a crashkernel= commandline parameter was not used when the currently running kernel booted. You will need to add a crashkernel= parameter to your /etc/lilo.conf, /etc/elilo.conf or grub /boot/grub/menu.lst file and reboot, before kdump will work. See installed READMEs for suggestions.
could not find an installed debug vmlinux image and DEBUG_KERNEL is not specified in /etc/default/kdump-tools Warning: makedumpfile will be limited to -d 1.
A debug version of the currently booted kernel could not
be found.
- KDUMP_KERNEL does not exist: $KDUMP_KERNEL
- A KDUMP_KERNEL was specified in /etc/default/kdump-tools, but it cannot be found.
- KDUMP_INITRD does not exist: $KDUMP_INITRD
- A KDUMP_INITRD was specified in /etc/default/kdump-tools, but it cannot be found.
no KDUMP_KERNEL in $KDUMP_DEFAULTS and can't find a kdump package directory in /usr/lib
no kdump kernel could be found.
found a linux-kdump package in $KDUMP_PKG_DIR but can't find a kdump kernel in $KDUMP_PKG_DIR
this indicates a broken linux-kdump package
installation.
no kdump initrd image: $KDUMP_INITRD an initrd will not be used
this indicates that although a kdump kernel was found, a
corresponding initrd was not found.
- kdump kernel relocation address does not match crashkernel= parameter
- For non-relocatable architectures, the kdump kernel must be built with a predetermined start address. This message indicates that the start address of the kdump kernel and the start address in the crashkernel= parameter do not match.
- failed to load kdump kernel
- kexec reported that it could not load the kdump kernel.
- failed to unload kdump kernel
- kexec reported that it could not unload the kdump kernel. Run 'kexec -u' directly for more detail.
- makedumpfile failed, falling back to 'cp'
- this message is printed if the kdump-tools init script attempts to save a /proc/vmcore file using makedumpfile and the save fails.
- failed to save vmcore in $KDUMP_STAMPDIR
- this message indicates that makedumpfile and the fallback method of using cp has failed. This usually occurs if pathnames are wrong or if the disk is full.
SEE ALSO¶
/usr/share/doc/kdump-tools/READMEAUTHOR¶
Terry Loftin <terry.loftin@hp.com>April 2007 | kdump-tools v1.1.3 |