1KDUMPCTL(8)                 System Manager's Manual                KDUMPCTL(8)
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NAME

6       kdumpctl - control interface for kdump
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SYNOPSIS

10       kdumpctl COMMAND
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DESCRIPTION

14       kdumpctl is used to check or control the kdump service.  In most cases,
15       you should use systemctl to start / stop /  enable  kdump  service  in‐
16       stead.  However,  kdumpctl  provides  more  details for debugging and a
17       helper to set up ssh key authentication.
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COMMANDS

21       start  Start the service.
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23       stop   Stop the service.
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25       status Prints the current status of kdump service.  It returns  a  non-
26              zero value if kdump is not operational.
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28       restart
29              Is equal to start; stop
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31       reload reload the crash kernel image and initramfs without triggering a
32              rebuild.
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34       rebuild
35              rebuild the crash kernel initramfs.
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37       propagate
38              Helps to setup key authentication for ssh storage since it's im‐
39              possible to use password authentication during kdump.
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41       showmem
42              Prints  the  size  of  reserved  memory  for the crash kernel in
43              megabytes.
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45       estimate
46              Estimate a suitable crashkernel value for the  current  machine.
47              This  is  a  best-effort  estimate.  It will print a recommended
48              crashkernel value based on the current  kdump  setup,  and  list
49              some details of memory usage.
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51       get-default-crashkernel
52              Return the default crashkernel value provided by kexec-tools.
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54       reset-crashkernel [--kernel=path_to_kernel] [--reboot]
55              Reset  crashkernel  to default value recommended by kexec-tools.
56              If no kernel is specified, will reset  KDUMP_KERNELVER  if  it's
57              defined  in /etc/sysconfig/kdump or the current running kernel's
58              crashkernel value if KDUMP_KERNELVER  is  empty.  You  can  also
59              specify  --kernel=ALL  and  --kernel=DEFAULT which have the same
60              meaning as  grubby's  kernel-path=ALL  and  kernel-path=DEFAULT.
61              ppc64le  supports  FADump  and  supports  an  additional [--fad‐
62              ump=[on|off|nocma]] parameter to toggle FADump on/off.
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64              Note: The memory requirements for kdump varies heavily depending
65              on  the  used hardware and system configuration. Thus the recom‐
66              mended crashkernel might  not  work  for  your  specific  setup.
67              Please  test  if  kdump  works  after  resetting the crashkernel
68              value.
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SEE ALSO

72       kdump.conf(5), mkdumprd(8)
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76kexec-tools                       2015-07-13                       KDUMPCTL(8)
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