HEX
Server: nginx/1.22.1
System: Linux VM-16-9-centos 3.10.0-1160.99.1.el7.x86_64 #1 SMP Wed Sep 13 14:19:20 UTC 2023 x86_64
User: www (1001)
PHP: 7.3.31
Disabled: passthru,exec,system,putenv,chroot,chgrp,chown,shell_exec,popen,proc_open,pcntl_exec,ini_alter,ini_restore,dl,openlog,syslog,readlink,symlink,popepassthru,pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,imap_open,apache_setenv
Upload Files
File: //lib/dracut/modules.d/98systemd/dracut-shutdown.service.8
'\" t
.\"     Title: dracut-shutdown.service
.\"    Author: [see the "AUTHORS" section]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: 09/12/2013
.\"    Manual: dracut
.\"    Source: dracut
.\"  Language: English
.\"
.TH "DRACUT\-SHUTDOWN\&.S" "8" "09/12/2013" "dracut" "dracut"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
dracut-shutdown.service \- unpack the initramfs to /run/initramfs
.SH "SYNOPSIS"
.sp
dracut\-shutdown\&.service
.SH "DESCRIPTION"
.sp
This service unpacks the initramfs image to /run/initramfs\&. systemd pivots into /run/initramfs at shutdown, so the root filesytem can be safely unmounted\&.
.sp
The following steps are executed during a shutdown:
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
systemd switches to the shutdown\&.target
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
systemd starts /lib/systemd/system/shutdown\&.target\&.wants/dracut\-shutdown\&.service
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
dracut\-shutdown\&.service executes /usr/lib/dracut/dracut\-initramfs\-restore which unpacks the initramfs to /run/initramfs
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
systemd finishes shutdown\&.target
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
systemd kills all processes
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
systemd tries to unmount everything and mounts the remaining read\-only
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
systemd checks, if there is a /run/initramfs/shutdown executable
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
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\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
shutdown will try to umount every /oldroot mount and calls the various shutdown hooks from the dracut modules
.RE
.sp
This ensures, that all devices are disassembled and unmounted cleanly\&.
.sp
To debug the shutdown process, you can get a shell in the shutdown procedure by injecting "rd\&.break=pre\-shutdown rd\&.shell" or "rd\&.break=shutdown rd\&.shell"\&.
.sp
.if n \{\
.RS 4
.\}
.nf
# mkdir \-p /run/initramfs/etc/cmdline\&.d
# echo "rd\&.break=pre\-shutdown rd\&.shell" > /run/initramfs/etc/cmdline\&.d/debug\&.conf
# touch /run/initramfs/\&.need_shutdown
.fi
.if n \{\
.RE
.\}
.SH "AUTHORS"
.sp
Harald Hoyer
.SH "SEE ALSO"
.sp
\fBdracut\fR(8)