[linux] what‘s the kdump?

• The defination of kdump?
  • https://docs.kernel.org/admin-guide/kdump/kdump.html
• How to use kdump?
  • https://opensource.com/article/17/6/kdump-usage-and-internals

kexec-tools

Compilation of kexec-tools source code provides an executable called kexec. The same executable can be used to load and execute a second kernel or to load a capture kernel, which can be executed upon kernel panic.

A typical command to load a second kernel:

# kexec -l kernel.img --initrd=initramfs-image.img –reuse-cmdline

--reuse-command line says to use the same command line as that of first kernel. Pass initramfs using --initrd . -l says that you are loading the second kernel, which can be executed by the kexec application itself (kexec -e ). A kernel loaded using -l cannot be executed at kernel panic. You must pass -p instead of -l to load the capture kernel that can be executed upon kernel panic.

A typical command to load a capture kernel:

# kexec -p kernel.img --initrd=initramfs-image.img –reuse-cmdline