51 lines
1.6 KiB
Plaintext
51 lines
1.6 KiB
Plaintext
DRACUT-SHUTDOWN.SERVICE(8)
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===========================
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:doctype: manpage
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:man source: dracut
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:man manual: dracut
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NAME
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----
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dracut-shutdown.service - unpack the initramfs to /run/initramfs
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SYNOPSIS
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--------
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dracut-shutdown.service
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DESCRIPTION
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-----------
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This service unpacks the initramfs image to /run/initramfs.
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systemd pivots into /run/initramfs at shutdown, so the root filesytem
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can be safely unmounted.
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The following steps are executed during a shutdown:
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* systemd switches to the shutdown.target
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* systemd starts /lib/systemd/system/shutdown.target.wants/dracut-shutdown.service
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* dracut-shutdown.service executes /usr/lib/dracut/dracut-initramfs-restore which unpacks the initramfs to /run/initramfs
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* systemd finishes shutdown.target
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* systemd kills all processes
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* systemd tries to unmount everything and mounts the remaining read-only
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* systemd checks, if there is a /run/initramfs/shutdown executable
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* if yes, it does a pivot_root to /run/initramfs and executes ./shutdown. The old root is then mounted on /oldroot. /usr/lib/dracut/modules.d/99shutdown/shutdown.sh is the shutdown executable.
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* shutdown will try to umount every /oldroot mount and calls the various shutdown hooks from the dracut modules
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This ensures, that all devices are disassembled and unmounted cleanly.
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To debug the shutdown process, you can get a shell in the shutdown procedure
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by injecting "rd.break=pre-shutdown rd.shell" or "rd.break=shutdown rd.shell".
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----
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# mkdir -p /run/initramfs/etc/cmdline.d
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# echo "rd.break=pre-shutdown rd.shell" > /run/initramfs/etc/cmdline.d/debug.conf
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# touch /run/initramfs/.need_shutdown
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----
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AUTHORS
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-------
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Harald Hoyer
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SEE ALSO
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--------
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*dracut*(8)
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