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 debug and a helper
17       to setup 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 non-zero
26              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 crash kernel image and initramfs without triggering a re‐
32              build.
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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  crash  kernel  in
43              megabytes.
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45       estimate
46              Estimate a suitable crashkernel value for current machine.  This
47              is a best-effort estimate. It will print a recommanded crashker‐
48              nel value based on current kdump setup, and list some details of
49              memory usage.
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51       reset-crashkernel [--kernel=path_to_kernel] [--reboot]
52              Reset  crashkernel  to default value recommended by kexec-tools.
53              If no kernel is specified, will reset  KDUMP_KERNELVER  if  it's
54              defined  in  /etc/sysconfig/kdump  or  current  running kernel's
55              crashkernel value if KDUMP_KERNELVER  is  empty.  You  can  also
56              specify  --kernel=ALL  and  --kernel=DEFAULT which have the same
57              meaning as  grubby's  kernel-path=ALL  and  kernel-path=DEFAULT.
58              ppc64le  supports  FADump  and  supports  an  additonal  [--fad‐
59              ump=[on|off|nocma]] parameter to toggle FADump on/off.
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61              Note: The memory requirements for kdump varies heavily depending
62              on  the  used hardware and system configuration. Thus the recom‐
63              mended crashkernel might  not  work  for  your  specific  setup.
64              Please  test  if  kdump  works  after  resetting the crashkernel
65              value.
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SEE ALSO

69       kdump.conf(5), mkdumprd(8)
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73kexec-tools                       2015-07-13                       KDUMPCTL(8)
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