(split) LDP v3.24 -> v3.29 の定型的な変更内容を反映。

[linuxjm/LDP_man-pages.git] / draft / man4 / initrd.4

.\" -*- nroff -*-
.\" This man-page is Copyright (C) 1997 John S. Kallal
.\"
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Permission is granted to copy and distribute modified versions of this
.\" manual under the conditions for verbatim copying, provided that the
.\" entire resulting derived work is distributed under the terms of a
.\" permission notice identical to this one.
.\"
.\" Since the Linux kernel and libraries are constantly changing, this
.\" manual page may be incorrect or out-of-date.  The author(s) assume no
.\" responsibility for errors or omissions, or for damages resulting from
.\" the use of the information contained herein.  The author(s) may not
.\" have taken the same level of care in the production of this manual,
.\" which is licensed free of charge, as they might when working
.\" professionally.
.\"
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and author(s) of this work.
.\"
.\" If the you wish to distribute versions of this work under other
.\" conditions than the above, please contact the author(s) at the following
.\" for permission:
.\"
.\"  John S. Kallal -
.\"     email: <kallal@voicenet.com>
.\"     mail: 518 Kerfoot Farm RD, Wilmington, DE 19803-2444, USA
.\"     phone: (302)654-5478
.\"
.\" $Id: initrd.4,v 1.1.1.1 1999/07/19 01:49:27 cvs Exp $
.\"
.\" Japanese Version Copyright (c) 1997,1998
.\"           ISHIKAWA Mutsumi, all rights reserved.
.\" Translated 1997-12-15, ISHIKAWA Mutsumi <ishikawa@linux.or.jp>
.\" Modified 1998-02-09, ISHIKAWA Mutsumi <ishikawa@linux.or.jp>
.\" Updated & Modified 2005-10-08, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\"
.TH INITRD 4 2010-09-04 "Linux" "Linux Programmer's Manual"
.\"O .SH NAME
.SH ̾Á°
.\"O initrd \- boot loader initialized RAM disk
initrd \- ¥Ö¡¼¥È¥í¡¼¥À¤Ë¤è¤Ã¤Æ½é´ü²½¤µ¤ì¤¿ RAM ¥Ç¥£¥¹¥¯
.\"O .SH CONFIGURATION
.SH ÀßÄê
.\"O The
.\"O .I /dev/initrd
.\"O is a read-only block device assigned
.\"O major number 1 and minor number 250.
.\"O Typically
.\"O .I /dev/initrd
.\"O is owned by
.\"O .I root.disk
.\"O with mode 0400 (read access by root only).
.\"O If the Linux system does not have
.\"O .I /dev/initrd
.\"O already created, it can be created with the following commands:
.I /dev/initrd
¤Ï¡¢¥á¥¸¥ã¡¼ÈÖ¹æ 1¡¢¥Þ¥¤¥Ê¡¼ÈÖ¹æ 250 ¤¬³ä¤êÅö¤Æ¤é¤ì¤¿
Æɤ߹þ¤ßÀìÍѤΥ֥í¥Ã¥¯¥Ç¥Ð¥¤¥¹¤Ç¤¢¤ë¡£
ÉáÄÌ¡¢
.I /dev/initrd
¤Î½êÍ­¼Ô¤Ï
.I root.disk
¤Ç¤¢¤ê¡¢¥â¡¼¥É¤Ï 400 (root ¤Î¤ß¤¬Æɤ߽Ф·²Äǽ) ¤Ç¤¢¤ë¡£
¤â¤·¡¢Linux ¥·¥¹¥Æ¥à¤ËºîÀ®ºÑ¤Î
.I /dev/initrd
¥Õ¥¡¥¤¥ë¤¬¤Ê¤«¤Ã¤¿¾ì¹ç¡¢°Ê²¼¤Î¥³¥Þ¥ó¥É¤ÇºîÀ®¤¹¤ë¤³¤È¤¬¤Ç¤­¤ë:
.nf
\fB
        mknod \-m 400 /dev/initrd b 1 250
        chown root:disk /dev/initrd
\fP
.fi
.PP
.\"O Also, support for both "RAM disk" and "Initial RAM disk"
.\"O (e.g.
.\"O .BR CONFIG_BLK_DEV_RAM=y
.\"O and
.\"O .BR CONFIG_BLK_DEV_INITRD=y )
.\"O must be compiled directly into the Linux kernel to use
.\"O .IR /dev/initrd .
.\"O When using
.\"O .IR /dev/initrd ,
.\"O the RAM disk driver cannot be loaded as a module.
¤Þ¤¿¡¢
.I /dev/initrd
¤ò»ÈÍѤ¹¤ë¤¿¤á¤Ë¤Ï¡¢
"RAM disk" ¤È "Initial RAM disk" ¤ÎξÊý¤Îµ¡Ç½¤¬
Linux ¥«¡¼¥Í¥ë¤ËľÀÜÁȤ߹þ¤Þ¤ì¤Æ¤¤¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤
(Î㤨¤Ð¡¢¥«¡¼¥Í¥ë¤Î¥³¥ó¥Ñ¥¤¥ë»þ¤ÎÀßÄê¤Ç
.B CONFIG_BLK_DEV_RAM=y
¤«¤Ä
.B CONFIG_BLK_DEV_INITRD=y
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.I /dev/initrd
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¥í¡¼¥É¤¹¤ë¤³¤È¤Ï¤Ç¤­¤Ê¤¤¡£
.\"
.\"
.\"
.\"O .SH DESCRIPTION
.SH ÀâÌÀ
.\"O The special file
.\"O .I /dev/initrd
.\"O is a read-only block device.
.\"O This device is a RAM disk that is initialized (e.g., loaded)
.\"O by the boot loader before the kernel is started.
.\"O The kernel then can use
.\"O .IR /dev/initrd "'s "
.\"O contents for a two-phase system boot-up.
.I /dev/initrd
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¤³¤Î¥Ç¥Ð¥¤¥¹¤Ï¥«¡¼¥Í¥ë¤¬µ¯Æ°¤µ¤ì¤ëÁ°¤Ë¥Ö¡¼¥È¥í¡¼¥À (boot loader)
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.I /dev/initrd
¤ÎÆâÍƤòÆóÃʳ¬¤Î¥·¥¹¥Æ¥àµ¯Æ° (two-phase system boot-up)
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.PP
.\"O In the first boot-up phase, the kernel starts up
.\"O and mounts an initial root file-system from the contents of
.\"O .I /dev/initrd
.\"O (e.g., RAM disk initialized by the boot loader).
.\"O In the second phase, additional drivers or other modules
.\"O are loaded from the initial root device's contents.
.\"O After loading the additional modules, a new root file system
.\"O (i.e., the normal root file system) is mounted from a
.\"O different device.
ºÇ½é¤Î¥Ö¡¼¥È¥¢¥Ã¥×Ãʳ¬ (first boot-up phase) ¤Ç¤Ï¡¢¥«¡¼¥Í¥ë¤Ï
(Î㤨¤Ð¡¢¥Ö¡¼¥È¥í¡¼¥À¤Ë¤è¤Ã¤Æ½é´ü²½¤µ¤ì¤¿ RAM disk ¤Ç¤¢¤ë)
.I /dev/initrd
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.\"
.\"
.\"
.\"O .SS "Boot-up Operation"
.SS ¥Ö¡¼¥È¥¢¥Ã¥×ºî¶È
.\"O When booting up with
.\"O .BR initrd ,
.\"O the system boots as follows:
.B initrd
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.IP 1. 3
.\"O The boot loader loads the kernel program and
.\"O .IR /dev/initrd 's
.\"O contents into memory.
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.IP 2.
.\"O On kernel startup,
.\"O the kernel uncompresses and copies the contents of the device
.\"O .I /dev/initrd
.\"O onto device
.\"O .I /dev/ram0
.\"O and then frees the memory used by
.\"O .IR /dev/initrd .
¥«¡¼¥Í¥ëµ¯Æ°»þ¡¢¥«¡¼¥Í¥ë¤Ï
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.I /dev/initrd
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.IP 3.
.\"O The kernel then read-write mounts the device
.\"O .I /dev/ram0
.\"O as the initial root file system.
¥«¡¼¥Í¥ë¤Ï
.I /dev/ram0
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.IP 4.
.\"O If the indicated normal root file system is also the initial
.\"O root file-system (e.g.
.\"O .IR /dev/ram0 )
.\"O then the kernel skips to the last step for the usual boot sequence.
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(Î㤨¤Ð
.IR /dev/ram0 )
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.IP 5.
.\"O If the executable file
.\"O .IR /linuxrc
.\"O is present in the initial root file-system,
.\"O .I /linuxrc
.\"O is executed with UID 0.
.\"O (The file
.\"O .I /linuxrc
.\"O must have executable permission.
.\"O The file
.\"O .I /linuxrc
.\"O can be any valid executable, including a shell script.)
.I /linuxrc
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.I /linuxrc
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.IP 6.
.\"O If
.\"O .I /linuxrc
.\"O is not executed or when
.\"O .I /linuxrc
.\"O terminates, the normal root file system is mounted.
.\"O (If
.\"O .I /linuxrc
.\"O exits with any file-systems mounted on the initial root
.\"O file-system, then the behavior of the kernel is
.\"O .BR UNSPECIFIED .
.\"O See the NOTES section for the current kernel behavior.)
.I /linuxrc
¤¬¼Â¹Ô¤µ¤ì¤Ê¤¤¡¢¤Þ¤¿¤Ï¡¢
.I /linuxrc
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.RI ( /linuxrc
¤ò½ªÎ»¤·¤¿»þ¡¢²¿¤é¤«¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤¬½é´ü¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¾å¤Ë
¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤ë¾ì¹ç¤Î¥«¡¼¥Í¥ë¤ÎÆ°ºî¤Ï
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.IP 7.
.\"O If the normal root file system has a directory
.\"O .IR /initrd ,
.\"O the device
.\"O .I /dev/ram0
.\"O is moved from
.\"O .IR /
.\"O to
.\"O .IR /initrd .
.\"O Otherwise if the directory
.\"O .IR /initrd
.\"O does not exist, the device
.\"O .I /dev/ram0
.\"O is unmounted.
.\"O (When moved from
.\"O .IR /
.\"O to
.\"O .IR /initrd ,
.\"O .I /dev/ram0
.\"O is not unmounted and therefore processes can remain running from
.\"O .IR /dev/ram0 .
.\"O If directory
.\"O .I /initrd
.\"O does not exist on the normal root file system
.\"O and any processes remain running from
.\"O .IR /dev/ram0
.\"O when
.\"O .I /linuxrc
.\"O \"O exits, the behavior of the kernel is
.\"O .BR UNSPECIFIED .
.\"O See the NOTES section for the current kernel behavior.)
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.IP 8.
.\"O The usual boot sequence (e.g., invocation of
.\"O .IR /sbin/init )
.\"O is performed on the normal root file system.
ÉáÄ̤Υ֡¼¥È¥·¡¼¥±¥ó¥¹ (Î㤨¤Ð¡¢
.I /sbin/init
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.\"
.\"
.\"
.\"O .SS Options
.SS ¥ª¥×¥·¥ç¥ó
.\"O The following boot loader options, when used with
.\"O .BR initrd ,
.\"O affect the kernel's boot-up operation:
.B initrd
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.TP
.\"O .BI initrd= "filename"
.\"O Specifies the file to load as the contents of
.\"O .IR /dev/initrd .
.\"O For
.\"O .B LOADLIN
.\"O this is a command-line option.
.\"O For
.\"O .B LILO
.\"O you have to use this command in the
.\"O .B LILO
.\"O configuration file
.\"O .IR /etc/lilo.config .
.\"O The filename specified with this
.\"O option will typically be a gzipped file-system image.
.BI initrd= "filename"
.I /dev/initrd
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.B LOADLIN
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.B LILO
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.B LILO
¤ÎÀßÄê¥Õ¥¡¥¤¥ë
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.TP
.\"O .I noinitrd
.\"O This boot option disables the two-phase boot-up operation.
.\"O The kernel performs the usual boot sequence as if
.\"O .I /dev/initrd
.\"O was not initialized.
.\"O With this option, any contents of
.\"O .I /dev/initrd
.\"O loaded into memory by the boot loader contents are preserved.
.\"O This option permits the contents of
.\"O .I /dev/initrd
.\"O to be any data and need not be limited to a file system image.
.\"O However, device
.\"O .I /dev/initrd
.\"O is read-only and can be read only one time after system startup.
.B noinitrd
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.TP
.\"O .BI root= "device-name"
.\"O Specifies the device to be used as the normal root file system.
.\"O .RB "For " LOADLIN
.\"O this is a command-line option.
.\"O .RB "For " LILO " this is a boot time option or
.\"O can be used as an option line in the
.\"O .B LILO
.\"O configuration file
.\"O .IR /etc/lilo.config .
.\"O The device specified by the this option must be a mountable
.\"O device having a suitable root file-system.
.BI root= "device-name"
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.B LOADLIN
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.B LILO
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.B LILO
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.I /etc/lilo.config
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.\"
.\"
.\"
.\"O .SS "Changing the Normal Root File System"
.SS Ä̾ï»þ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ÎÊѹ¹
.\"O By default,
.\"O the kernel's settings
.\"O (e.g., set in the kernel file with
.\"O .BR rdev (8)
.\"O or compiled into the kernel file),
.\"O or the boot loader option setting
.\"O is used for the normal root file systems.
.\"O For an NFS-mounted normal root file system, one has to use the
.\"O .B nfs_root_name
.\"O and
.\"O .B nfs_root_addrs
.\"O boot options to give the NFS settings.
.\"O For more information on NFS-mounted root see the kernel documentation file
.\"O .BR Documentation/filesystems/nfsroot.txt .
.\"O For more information on setting the root file system see also the
.\"O .BR LILO
.\"O and
.\"O .BR LOADLIN
.\"O documentation.
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.B Documentation/filesystems/nfsroot.txt
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.B LILO
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.B LOADLIN
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.\"O It is also possible for the
.\"O .I /linuxrc
.\"O executable to change the normal root device.
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.\"O For
.\"O .I /linuxrc
.\"O to change the normal root device,
.\"O .IR /proc
.\"O must be mounted.
.I /linuxrc
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.\"O After mounting
.\"O .IR /proc ,
.\"O .I /linuxrc
.\"O changes the normal root device by writing into the proc files
.\"O .IR /proc/sys/kernel/real-root-dev ,
.\"O .IR /proc/sys/kernel/nfs-root-name ,
.\"O and
.\"O .IR /proc/sys/kernel/nfs-root-addrs .
.I /proc
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.\"O For a physical root device, the root device is changed by having
.\"O .I /linuxrc
.\"O write the new root file system device number into
.\"O .IR /proc/sys/kernel/real-root-dev .
(NFS ¤Ç¤Ï¤Ê¤¤) ʪÍýŪ¤Ê¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤Î¾ì¹ç¡¢
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.\"O For an NFS root file system, the root device is changed by having
.\"O .I /linuxrc
.\"O write the NFS setting into files
.\"O .IR /proc/sys/kernel/nfs-root-name
.\"O and
.\"O .I /proc/sys/kernel/nfs-root-addrs
.\"O and then writing 0xff (e.g., the pseudo-NFS-device number) into file
.\"O .IR /proc/sys/kernel/real-root-dev .
NFS ¥ë¡¼¥È¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¾ì¹ç¡¢
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.\"O For example, the following shell command line would change
.\"O the normal root device to
.\"O .IR /dev/hdb1 :
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.I /dev/hdb1
¤ËÊѹ¹¤Ç¤­¤ë¤À¤í¤¦:
.nf

    echo 0x365 >/proc/sys/kernel/real-root-dev

.fi
.\"O For an NFS example, the following shell command lines would change the
.\"O normal root device to the NFS directory
.\"O .I /var/nfsroot
.\"O on a local networked NFS server with IP number 193.8.232.7 for a system with
.\"O IP number 193.8.232.2 and named "idefix":
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¥·¥¹¥Æ¥à¤Î¡¢Ä̾ï»þ¥ë¡¼¥È¥Ç¥Ð¥¤¥¹¤È¤·¤Æ¡¢
¥í¡¼¥«¥ë¥Í¥Ã¥È¥ï¡¼¥¯¤Î 193.8.232.2 ¤È¤¤¤¦ IP ¥¢¥É¥ì¥¹¤ò»ý¤Ä NFS ¥µ¡¼¥Ð¤Î
NFS ¥Ç¥£¥ì¥¯¥È¥ê
.I /var/nfsroot
¤ò¥Þ¥¦¥ó¥È¤¹¤ë¤è¤¦¤ËÊѹ¹¤Ç¤­¤ë:
.nf

    echo /var/nfsroot >/proc/sys/kernel/nfs-root-name
    echo 193.8.232.2:193.8.232.7::255.255.255.0:idefix \\
        >/proc/sys/kernel/nfs-root-addrs
    echo 255 >/proc/sys/kernel/real-root-dev
.fi

.\"O .BR Note :
.BR Ãí°Õ :
.\"O The use of
.\"O .I /proc/sys/kernel/real-root-dev
.\"O to change the root file system is obsolete.
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.I /proc/sys/kernel/real-root-dev
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.\"O See the kernel source file
.\"O .I Documentation/initrd.txt
.\"O as well as
.\"O .BR pivot_root (2)
.\"O and
.\"O .BR pivot_root (8)
.\"O for information on the modern method of changing the root file system.
.\"O .\" FIXME the manual page should describe the pivot_root mechanism.
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¥«¡¼¥Í¥ë¥½¡¼¥¹¤Ë´Þ¤Þ¤ì¤ë
.I Documentation/initrd.txt
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.BR pivot_root (2)
¤ä
.BR pivot_root (8)
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.\"
.\"
.\"
.\"O .SS Usage
.SS »È¤¤Êý
.\"O The main motivation for implementing
.\"O .B initrd
.\"O was to allow for modular kernel configuration at system installation.
.B initrd
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.\"O A possible system installation scenario is as follows:
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.IP 1. 3
.\"O The loader program boots from floppy or other media with a minimal kernel
.\"O (e.g., support for
.\"O .IR /dev/ram ,
.\"O .IR /dev/initrd ,
.\"O and the ext2 file-system) and loads
.\"O .IR /dev/initrd
.\"O with a gzipped version of the initial file-system.
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.IR /dev/ram ,
.IR /dev/initrd ,
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gzip °µ½Ì¤µ¤ì¤¿½é´ü¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¥¤¥á¡¼¥¸¤ò
.I /dev/initrd
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.\"O The executable
.\"O .I /linuxrc
.\"O determines what is needed to (1) mount the normal root file-system
.\"O (i.e., device type, device drivers, file system) and (2) the
.\"O distribution media (e.g., CD-ROM, network, tape, ...).
.\"O This can be done by asking the user, by auto-probing,
.\"O or by using a hybrid approach.
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.\"O The executable
.\"O .I /linuxrc
.\"O loads the necessary modules from the initial root file-system.
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.\"O The executable
.\"O .I /linuxrc
.\"O creates and populates the root file system.  (At this stage the normal
.\"O root file system does not have to be a
.\"O completed system yet.)
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.\"O The executable
.\"O .IR /linuxrc
.\"O sets
.\"O .IR /proc/sys/kernel/real-root-dev ,
.\"O unmount
.\"O .IR /proc ,
.\"O the normal root file system and any other file
.\"O systems it has mounted, and then terminates.
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.\"O The kernel then mounts the normal root file system.
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.\"O Now that the file system is accessible and intact,
.\"O the boot loader can be installed.
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.\"O The boot loader is configured to load into
.\"O .I /dev/initrd
.\"O a file system with the set of modules that was used to bring up the system.
.\"O (e.g., Device
.\"O .I /dev/ram0
.\"O can be modified, then unmounted, and finally, the image is written from
.\"O .I /dev/ram0
.\"O to a file.)
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.\"O The system is now bootable and additional installation tasks can be
.\"O performed.
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.\"O The key role of
.\"O .I /dev/initrd
.\"O in the above is to reuse the configuration data during normal system operation
.\"O without requiring initial kernel selection, a large generic kernel or,
.\"O recompiling the kernel.
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.\"O A second scenario is for installations where Linux runs on systems with
.\"O different hardware configurations in a single administrative network.
.\"O In such cases, it may be desirable to use only a small set of kernels
.\"O (ideally only one) and to keep the system-specific part of configuration
.\"O information as small as possible.
.\"O In this case, create a common file
.\"O with all needed modules.
.\"O Then, only the
.\"O .I /linuxrc
.\"O file or a file executed by
.\"O .I /linuxrc
.\"O would be different.
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.\"O A third scenario is more convenient recovery disks.
.\"O Because information like the location of the root file-system
.\"O partition is not needed at boot time, the system loaded from
.\"O .I /dev/initrd
.\"O can use a dialog and/or auto-detection followed by a
.\"O possible sanity check.
3 ÈÖÌܤΥ±¡¼¥¹¤Ï¡¢¤è¤êÊØÍø¤ÊÉüµìÍѥǥ£¥¹¥¯¤òºî¤ë¾ì¹ç¤Ç¤¢¤ë¡£
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.\"O Last but not least, Linux distributions on CD-ROM may use
.\"O .B initrd
.\"O for easy installation from the CD-ROM.
.\"O The distribution can use
.\"O .B LOADLIN
.\"O to directly load
.\"O .I /dev/initrd
.\"O from CD-ROM without the need of any floppies.
.\"O The distribution could also use a
.\"O .B LILO
.\"O boot floppy and then bootstrap a bigger RAM disk via
.\"O .IR /dev/initrd
.\"O from the CD-ROM.
(¾¤Ë¤â¤¿¤¯¤µ¤óÎ㤬¤¢¤ë¤À¤í¤¦¤¬) ºÇ¸å¤ÎÎã¤È¤·¤Æ¤Ï¡¢
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¤ò»È¤Ã¤Æ¡¢¥Õ¥í¥Ã¥Ô¡¼¤òÁ´¤¯ÍøÍѤ»¤º¤Ë CD-ROM ¤«¤é
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.\"
.\"
.\"
.\"O .SH FILES
.SH ¥Õ¥¡¥¤¥ë
.I /dev/initrd
.br
.I /dev/ram0
.br
.I /linuxrc
.br
.I /initrd
.\"
.\"
.\"
.\"O .SH NOTES
.SH Ãí°Õ
.IP 1. 3
.\"O With the current kernel, any file systems that remain mounted when
.\"O .I /dev/ram0
.\"O is moved from
.\"O .I /
.\"O to
.\"O .I /initrd
.\"O continue to be accessible.
.\"O However, the
.\"O .I /proc/mounts
.\"O entries are not updated.
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.\"O With the current kernel, if directory
.\"O .I /initrd
.\"O does not exist, then
.\"O .I /dev/ram0
.\"O will
.\"O .B not
.\"O be fully unmounted if
.\"O .I /dev/ram0
.\"O is used by any process or has any file-system mounted on it.
.\"O If
.\"O .IR /dev/ram0
.\"O is
.\"O .B not
.\"O fully unmounted, then
.\"O .I /dev/ram0
.\"O will remain in memory.
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.\"O Users of
.\"O .I /dev/initrd
.\"O should not depend on the behavior give in the above notes.
.\"O The behavior may change in future versions of the Linux kernel.
.I /dev/initrd
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.\"
.\"
.\"
.\"O .\" .SH AUTHOR
.\" .SH Ãø¼Ô
.\"O .\" The kernel code for device
.\"O .\" .BR initrd
.\"O .\" was written by Werner Almesberger <almesber@lrc.epfl.ch> and
.\"O .\" Hans Lermen <lermen@elserv.ffm.fgan.de>.
.\" .BR initrd
.\" ¥Ç¥Ð¥¤¥¹¤Î¤¿¤á¤Î¥«¡¼¥Í¥ë¥³¡¼¥É¤Ï Werner Almesberger <almesber@lrc.epfl.ch>
.\" ¤È Hans Lermen <lermen@elserv.ffm.fgan.de> ¤Ë¤è¤Ã¤Æ½ñ¤«¤ì¤¿¡£
.\"O .\" The code for
.\"O .\" .BR initrd
.\"O .\" was added to the baseline Linux kernel in development version 1.3.73.
.\" .BR initrd
.\" ¤Î¤¿¤á¤Î¥³¡¼¥É¤Ï¡¢³«È¯¼Ô¸þ¤±¥Ð¡¼¥¸¥ç¥ó¤Î 1.3.73 ¤Ç
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.\"O .SH "SEE ALSO"
.SH ´ØÏ¢¹àÌÜ
.BR chown (1),
.BR mknod (1),
.BR ram (4),
.BR freeramdisk (8),
.BR rdev (8)

.\"O The documentation file
.\"O .I initrd.txt
.\"O in the kernel source package, the LILO documentation,
.\"O the LOADLIN documentation, the SYSLINUX documentation.
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