xref: /dragonfly/etc/rc.d/initdiskless (revision de78d61c)
1#!/bin/sh
2#
3# Copyright (c) 1999  Matt Dillon
4# All rights reserved.
5#
6# Redistribution and use in source and binary forms, with or without
7# modification, are permitted provided that the following conditions
8# are met:
9# 1. Redistributions of source code must retain the above copyright
10#    notice, this list of conditions and the following disclaimer.
11# 2. Redistributions in binary form must reproduce the above copyright
12#    notice, this list of conditions and the following disclaimer in the
13#    documentation and/or other materials provided with the distribution.
14#
15# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25# SUCH DAMAGE.
26#
27# $FreeBSD: src/etc/rc.d/initdiskless,v 1.24 2003/06/30 21:47:06 brooks Exp $
28#
29# PROVIDE: initdiskless
30
31. /etc/rc.subr
32dummy_rc_command "$1"
33
34# On entry to this script the entire system consists of a read-only root
35# mounted via NFS.  We use the contents of /conf to create and populate
36# memory filesystems.  The kernel has run BOOTP and configured an interface
37# (otherwise it would not have been able to mount the NFS root!)
38#
39# The following directories are scanned.  Each successive directory overrides
40# (is merged into) the previous one.
41#
42#	/conf/base		universal base
43#	/conf/default		modified by a secondary universal base
44#	/conf/${ipbca}		modified based on the assigned broadcast IP
45#	/conf/${ipa}		modified based on the machine's assigned IP
46#
47# If a directory contains the file 'remount', the contents of the file is
48# used to remount the directory. For example, if /conf/base/remount contains
49# the string 'my.server.com:/new_conf' then my.server.com:/new_conf will be
50# mounted in place of the directory.
51#
52# Each of these directories may contain any number of subdirectories which
53# represent directories in / on the diskless machine.  The existence of
54# these subdirectories causes this script to create a MEMORY FILESYSTEM for
55# /<sub_directory_name>.  For example, if /conf/base/etc exists then a
56# memory filesystem will be created for /etc.
57#
58# If a subdirectory contains the file 'diskless_remount' the contents of
59# the file is used to remount the subdirectory prior to it being copied to
60# the memory filesystem.  For example, if /conf/base/etc/diskless_remount
61# contains the string 'my.server.com:/etc' then my.server.com:/etc will be
62# mounted in place of the subdirectory.  This allows you to avoid making
63# duplicates of system directories in /conf.
64#
65# If a subdirectory contains the file 'md_size', the contents of the
66# file is used to determine the size of the memory filesystem, in 512
67# byte sectors.  The default is 4096 (2MB).  You only have to specify an
68# md_size if the default doesn't work for you (i.e. if it is too big or
69# too small).  For example, /conf/base/etc/md_size might contain '16384'.
70#
71# If /conf/<special_dir>/SUBDIR.cpio.gz exists, the file is cpio'd into
72# the specified /SUBDIR (and a memory filesystem is created for /SUBDIR
73# if necessary).
74#
75# If /conf/<special_dir>/SUBDIR.remove exists, the file contains a list
76# of paths which are rm -rf'd relative to /SUBDIR.
77#
78# You will almost universally want to create a /conf/base/etc containing
79# a diskless_remount and possibly an md_size file.  You will then almost
80# universally want to override rc.conf, rc.local, and fstab by creating
81# /conf/default/etc/{rc.conf,rc.local,fstab}.  Your fstab should be sure
82# to mount a /usr... typically an NFS readonly /usr.
83#
84# NOTE!  rc.d/diskless will create /var, /tmp, and /dev.  Those filesystems
85# should not be specified in /conf.  At least not yet.
86
87dlv=`${SYSCTL_N} -q vfs.nfs.diskless_valid`
88[ ${dlv:=0} -eq 0 ] && exit 0
89
90# chkerr:
91#
92# Routine to check for error
93#
94#	checks error code and drops into shell on failure.
95#	if shell exits, terminates script as well as /etc/rc.
96#
97chkerr() {
98	case $1 in
99	0)
100	;;
101	*)
102	echo "$2 failed: dropping into /bin/sh"
103	/bin/sh
104	# RESUME
105	;;
106	esac
107}
108
109# Create a generic memory disk
110#
111mount_md() {
112	/sbin/mount_tmpfs -s $1 tmpfs $2
113}
114
115# Create the memory filesystem if it has not already been created
116#
117create_md() {
118	if [ "x`eval echo \\$md_created_$1`" = "x" ]; then
119		if [ "x`eval echo \\$md_size_$1`" = "x" ]; then
120			if [ "$1" = "etc" ]; then
121				md_size=12M
122			else
123				md_size=2M
124			fi
125		else
126			md_size=`eval echo \\$md_size_$1`
127
128			# for backwards compatibility...
129			# if it's a number, then treat it as number of sectors
130			#
131			if [ "$md_size" = "${md_size%%[!0-9]*}" ]; then
132				md_size=`expr $md_size '*' 512`
133			fi
134		fi
135		mount_md $md_size /$1
136		/bin/chmod 755 /$1
137		eval md_created_$1=created
138	fi
139}
140
141# DEBUGGING
142#
143# set -v
144
145# Figure out our interface and IP.
146#
147bootp_ifc=""
148bootp_ipa=""
149bootp_ipbca=""
150iflist=`ifconfig -l`
151for i in ${iflist} ; do
152	set `ifconfig ${i}`
153	while [ $# -ge 1 ] ; do
154		if [ "${bootp_ifc}" = "" -a "$1" = "inet" ] ; then
155			bootp_ifc=${i} ; bootp_ipa=${2} ; shift
156		fi
157		if [ "${bootp_ipbca}" = "" -a "$1" = "broadcast" ] ; then
158			bootp_ipbca=$2; shift
159		fi
160		shift
161	done
162	if [ "${bootp_ifc}" != "" ] ; then
163		break
164	fi
165done
166echo "Interface ${bootp_ifc} IP-Address ${bootp_ipa} Broadcast ${bootp_ipbca}"
167
168# Figure out our NFS root path
169#
170set `mount -t nfs`
171while [ $# -ge 1 ] ; do
172	if [ "$2" = "on" -a "$3" = "/" ]; then
173		nfsroot="$1"
174		break
175	fi
176	shift
177done
178
179# Resolve templates in /conf/base, /conf/default, /conf/${bootp_ipbca},
180# and /conf/${bootp_ipa}.  For each subdirectory found within these
181# directories:
182#
183# - calculate memory filesystem sizes.  If the subdirectory (prior to
184#   NFS remounting) contains the file 'md_size', the contents specified
185#   in 512 byte sectors will be used to size the memory filesystem.
186#
187# - handle NFS remounts.  If the subdirectory contains the file
188#   diskless_remount, the contents of the file is NFS mounted over
189#   the directory.  For example /conf/base/etc/diskless_remount
190#   might contain 'myserver:/etc'.  NFS remounts allow you to avoid
191#   having to dup your system directories in /conf.  Your server must
192#   be sure to export those filesystems -alldirs, however.
193#   If the diskless_remount file contains a string beginning with a
194#   '/' it is assumed that the local nfsroot should be prepended to
195#   it before attemping to the remount.  This allows the root to be
196#   relocated without needing to change the remount files.
197#
198for i in base default ${bootp_ipbca} ${bootp_ipa} ; do
199	if [ -f /conf/$i/remount ]; then
200		nfspt=`/bin/cat /conf/$i/remount`
201		if [ `expr "$nfspt" : '\(.\)'` = "/" ]; then
202			nfspt="${nfsroot}${nfspt}"
203		fi
204		mount_nfs $nfspt /conf/$i
205		chkerr $? "mount_nfs $nfspt /conf/$i"
206	fi
207
208	for j in /conf/$i/* ; do
209		# memory filesystem size specification
210		#
211		subdir=${j##*/}
212		if [ -d $j -a -f $j/md_size ]; then
213			eval md_size_$subdir=`cat $j/md_size`
214		fi
215
216		# NFS remount
217		#
218		if [ -d $j -a -f $j/diskless_remount ]; then
219			nfspt=`/bin/cat $j/diskless_remount`
220			if [ `expr "$nfspt" : '\(.\)'` = "/" ]; then
221				nfspt="${nfsroot}${nfspt}"
222			fi
223			mount_nfs $nfspt $j
224			chkerr $? "mount_nfs $nfspt $j"
225		fi
226	done
227done
228
229# - Create all required TMPFS filesystems and populate them from
230#   our templates.  Support both a direct template and a dir.cpio.gz
231#   archive.  Support dir.remove files containing a list of relative
232#   paths to remove.
233#
234# TODO:
235#   + find a way to assign a 'group' identifier to a machine
236#	so we can use group-specific configurations;
237
238for i in base default ${bootp_ipbca} ${bootp_ipa} ; do
239	for j in /conf/$i/* ; do
240	subdir=${j##*/}
241	if [ -d $j ]; then
242		create_md $subdir
243		cp -Rp $j/* /$subdir
244	fi
245	done
246	for j in /conf/$i/*.cpio.gz ; do
247		subdir=${j%*.cpio.gz}
248		subdir=${subdir##*/}
249		if [ -f $j ]; then
250			create_md $subdir
251			echo "Loading /$subdir from cpio archive $j"
252			(cd /$subdir ; /usr/bin/cpio --extract -d -F $j )
253		fi
254	done
255	for j in /conf/$i/*.remove ; do
256		subdir=${j%*.remove}
257		subdir=${subdir##*/}
258		if [ -f $j ]; then
259			# doubly sure it is a memory disk before rm -rf'ing
260			create_md $subdir
261			(cd /$subdir; rm -rf `/bin/cat $j`)
262		fi
263	done
264done
265