1KDUMPCTL(8) System Manager's Manual KDUMPCTL(8)
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6 kdumpctl - control interface for kdump
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10 kdumpctl COMMAND
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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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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
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72 kdump.conf(5), mkdumprd(8)
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76kexec-tools 2015-07-13 KDUMPCTL(8)