Minor discovery: Ubuntu restarts the system with kexec

Kexec uses the overwrite philosophy of exec () called by Unix systems. It generates a new kernel that overwrites the running kernel. In this process, you do not need to start the firmware on the machine (firmware), so you can save some restart time. Because you need to check the bus and identify the device to start the firmware, saving the time will accelerate the system startup. If you know this, we can solve the problem that my system cannot be restarted. How can this problem be solved? 1. grep:/etc directory apple @ Ubunt

Kexec uses the overwrite philosophy of exec () called by Unix systems. It generates a new kernel that overwrites the running kernel. In this process, you do not need to start the firmware on the machine (firmware), so you can save some restart time.

Because you need to check the bus and identify the device to start the firmware, saving the time will accelerate the system startup.

After knowing this, let's solve the problem that my system cannot be restarted,

Why cannot it be started?

1. grep/etc directory

Apple @ Ubuntu :~ $ Sudo grep-r kexec/etc
Grep:/etc/alternatives/smbstatus.1.gz: No such file or directory
/Etc/rc6.d/K18kexec-load: # Provides: kexec-load
/Etc/rc6.d/K18kexec-load: # Required-Stop: $ remote_fs kexec
/Etc/rc6.d/K18kexec-load: # Short-Description: Load kernel image with kexec
/Etc/rc6.d/K18kexec-load: test-r/etc/default/kexec &./etc/default/kexec
/Etc/rc6.d/K18kexec-load: test-x/sbin/kexec | exit 0
/Etc/rc6.d/K18kexec-load: test "x 'cat/sys/kernel/kexec_loaded 'y" = "x1y" & exit 0
/Etc/rc6.d/K18kexec-load: kexec-l "$ KERNEL_IMAGE" -- append = "$ REAL_APPEND"
/Etc/rc6.d/K18kexec-load: kexec-l "$ KERNEL_IMAGE" -- initrd = "$ INITRD" -- append = "$ REAL_APPEND"
/Etc/rc6.d/S85kexec: # Provides: kexec
/Etc/rc6.d/S85kexec: # Short-Description: Execute the kexec-e command to reboot system
/Etc/rc6.d/S85kexec: test-r/etc/default/kexec &./etc/default/kexec
/Etc/rc6.d/S85kexec: test "x 'cat/sys/kernel/kexec_loaded 'y" = "x1y" | exit 0
/Etc/rc6.d/S85kexec: test-x/sbin/kexec | exit 0
/Etc/rc6.d/S85kexec: log_action_msg "Will now restart with kexec"
/Etc/rc6.d/S85kexec: kexec-e
/Etc/rc6.d/S85kexec: log_failure_msg "kexec failed"
/Etc/rc6.d/S60umountroot: # shocould-Stop: halt reboot kexec
/Etc/init. d/kexec-load: # Provides: kexec-load
/Etc/init. d/kexec-load: # Required-Stop: $ remote_fs kexec
/Etc/init. d/kexec-load: # Short-Description: Load kernel image with kexec
/Etc/init. d/kexec-load: test-r/etc/default/kexec &./etc/default/kexec
/Etc/init. d/kexec-load: test-x/sbin/kexec | exit 0
/Etc/init. d/kexec-load: test "x 'cat/sys/kernel/kexec_loaded 'y" = "x1y" & exit 0
/Etc/init. d/kexec-load: kexec-l "$ KERNEL_IMAGE" -- append = "$ REAL_APPEND"
/Etc/init. d/kexec-load: kexec-l "$ KERNEL_IMAGE" -- initrd = "$ INITRD" -- append = "$ REAL_APPEND"
/Etc/init. d/kexec: # Provides: kexec
/Etc/init. d/kexec: # Short-Description: Execute the kexec-e command to reboot system
/Etc/init. d/kexec: test-r/etc/default/kexec &./etc/default/kexec
/Etc/init. d/kexec: test "x 'cat/sys/kernel/kexec_loaded 'y" = "x1y" | exit 0
/Etc/init. d/kexec: test-x/sbin/kexec | exit 0
/Etc/init. d/kexec: log_action_msg "Will now restart with kexec"
/Etc/init. d/kexec: kexec-e
/Etc/init. d/kexec: log_failure_msg "kexec failed"
/Etc/init. d/umountroot: # shocould-Stop: halt reboot kexec
/Etc/init. d/kdump: # Short-Description: Load crashkernel image with kexec
/Etc/init. d/kdump: test-x/sbin/kexec | exit 0
/Etc/init. d/kdump: kexec-p "$ KERNEL_IMAGE" -- initrd = "$ INITRD" -- append = "$ APPEND"
/Etc/rc2.d/S00kdump: # Short-Description: Load crashkernel image with kexec
/Etc/rc2.d/S00kdump: test-x/sbin/kexec | exit 0
/Etc/rc2.d/S00kdump: kexec-p "$ KERNEL_IMAGE" -- initrd = "$ INITRD" -- append = "$ APPEND"
/Etc/default/kexec: # Defaults for kexec initscript
/Etc/default/kexec: # sourced by/etc/init. d/kexec and/etc/init. d/kexec-load
/Etc/default/kexec: # Load a kexec kernel (true/false)
/Etc/rc0.d/S60umountroot: # shocould-Stop: halt reboot kexec
Apple @ ubuntu :~ $

It seems that the script/etc/init. d/kexec needs to be used to restart the system.