xref: /dragonfly/etc/rc.d/initdiskless (revision 6b5c5d0d)
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# $DragonFly: src/etc/rc.d/initdiskless,v 1.8 2007/04/26 23:34:27 dillon Exp $
29#
30# PROVIDE: initdiskless
31
32. /etc/rc.subr
33dummy_rc_command "$1"
34
35# On entry to this script the entire system consists of a read-only root
36# mounted via NFS.  We use the contents of /conf to create and populate
37# memory filesystems.  The kernel has run BOOTP and configured an interface
38# (otherwise it would not have been able to mount the NFS root!)
39#
40# The following directories are scanned.  Each successive directory overrides
41# (is merged into) the previous one.
42#
43#	/conf/base		universal base
44#	/conf/default		modified by a secondary universal base
45#	/conf/${ipba}		modified based on the assigned broadcast IP
46#	/conf/${ip}		modified based on the machine's assigned IP
47#
48# Each of these directories may contain any number of subdirectories which
49# represent directories in / on the diskless machine.  The existance of
50# these subdirectories causes this script to create a MEMORY FILESYSTEM for
51# /<sub_directory_name>.  For example, if /conf/base/etc exists then a
52# memory filesystem will be created for /etc.
53#
54# If a subdirectory contains the file 'diskless_remount' the contents of
55# the file is used to remount the subdirectory prior to it being copied to
56# the memory filesystem.  For example, if /conf/base/etc/diskless_remount
57# contains the string 'my.server.com:/etc' then my.server.com:/etc will be
58# mounted in place of the subdirectory.  This allows you to avoid making
59# duplicates of system directories in /conf.
60#
61# If a subdirectory contains the file 'md_size', the contents of the
62# file is used to determine the size of the memory filesystem, in 512
63# byte sectors.  The default is 4096 (2MB).  You only have to specify an
64# md_size if the default doesn't work for you (i.e. if it is too big or
65# too small).  For example, /conf/base/etc/md_size might contain '16384'.
66#
67# If /conf/<special_dir>/SUBDIR.cpio.gz exists, the file is cpio'd into
68# the specified /SUBDIR (and a memory filesystem is created for /SUBDIR
69# if necessary).
70#
71# If /conf/<special_dir>/SUBDIR.remove exists, the file contains a list
72# of paths which are rm -rf'd relative to /SUBDIR.
73#
74# You will almost universally want to create a /conf/base/etc containing
75# a diskless_remount and possibly an md_size file.  You will then almost
76# universally want to override rc.conf, rc.local, and fstab by creating
77# /conf/default/etc/{rc.conf,rc.local,fstab}.  Your fstab should be sure
78# to mount a /usr... typically an NFS readonly /usr.
79#
80# NOTE!  rc.d/diskless will create /var, /tmp, and /dev.  Those filesystems
81# should not be specified in /conf.  At least not yet.
82
83dlv=`/sbin/sysctl -n vfs.nfs.diskless_valid 2> /dev/null`
84[ ${dlv:=0} -eq 0 ] && exit 0
85
86# chkerr:
87#
88# Routine to check for error
89#
90#	checks error code and drops into shell on failure.
91#	if shell exits, terminates script as well as /etc/rc.
92#
93chkerr() {
94	case $1 in
95	0)
96	;;
97	*)
98	echo "$2 failed: dropping into /bin/sh"
99	/bin/sh
100	# RESUME
101	;;
102	esac
103}
104
105# Create a generic memory disk
106#
107mount_md() {
108	/sbin/mount_mfs -i 4096 -s $1 swap $2
109}
110
111# Create the memory filesystem if it has not already been created
112#
113create_md() {
114	if [ "x`eval echo \\$md_created_$1`" = "x" ]; then
115		if [ "x`eval echo \\$md_size_$1`" = "x" ]; then
116			md_size=4096
117		else
118			md_size=`eval echo \\$md_size_$1`
119		fi
120		mount_md $md_size /$1
121		/bin/chmod 755 /$1
122		eval md_created_$1=created
123	fi
124}
125
126# DEBUGGING
127#
128# set -v
129
130# Figure out our interface and IP.
131#
132bootp_ifc=""
133bootp_ipa=""
134bootp_ipbca=""
135iflist=`ifconfig -l`
136for i in ${iflist} ; do
137	set `ifconfig ${i}`
138	while [ $# -ge 1 ] ; do
139		if [ "${bootp_ifc}" = "" -a "$1" = "inet" ] ; then
140			bootp_ifc=${i} ; bootp_ipa=${2} ; shift
141		fi
142		if [ "${bootp_ipbca}" = "" -a "$1" = "broadcast" ] ; then
143			bootp_ipbca=$2; shift
144		fi
145		shift
146	done
147	if [ "${bootp_ifc}" != "" ] ; then
148		break
149	fi
150done
151echo "Interface ${bootp_ifc} IP-Address ${bootp_ipa} Broadcast ${bootp_ipbca}"
152
153# Figure out our NFS root path
154#
155set `mount -t nfs`
156while [ $# -ge 1 ] ; do
157	if [ "$2" = "on" -a "$3" = "/" ]; then
158		nfsroot="$1"
159		break
160	fi
161	shift
162done
163
164# Resolve templates in /conf/base, /conf/default, /conf/${bootp_ipbca},
165# and /conf/${bootp_ipa}.  For each subdirectory found within these
166# directories:
167#
168# - calculate memory filesystem sizes.  If the subdirectory (prior to
169#   NFS remounting) contains the file 'md_size', the contents specified
170#   in 512 byte sectors will be used to size the memory filesystem.
171#
172# - handle NFS remounts.  If the subdirectory contains the file
173#   diskless_remount, the contents of the file is NFS mounted over
174#   the directory.  For example /conf/base/etc/diskless_remount
175#   might contain 'myserver:/etc'.  NFS remounts allow you to avoid
176#   having to dup your system directories in /conf.  Your server must
177#   be sure to export those filesystems -alldirs, however.
178#   If the diskless_remount file contains a string beginning with a
179#   '/' it is assumed that the local nfsroot should be prepended to
180#   it before attemping to the remount.  This allows the root to be
181#   relocated without needing to change the remount files.
182#
183for i in base default ${bootp_ipbca} ${bootp_ipa} ; do
184	for j in /conf/$i/* ; do
185	# memory filesystem size specification
186	#
187	subdir=${j##*/}
188	if [ -d $j -a -f $j/md_size ]; then
189		eval md_size_$subdir=`cat $j/md_size`
190	fi
191
192	# NFS remount
193	#
194	if [ -d $j -a -f $j/diskless_remount ]; then
195		nfspt=`/bin/cat $j/diskless_remount`
196		if [ `expr "$nfspt" : '\(.\)'` = "/" ]; then
197			nfspt="${nfsroot}${nfspt}"
198		fi
199		mount_nfs $nfspt $j
200		chkerr $? "mount_nfs $nfspt $j"
201	fi
202	done
203done
204
205# - Create all required MFS filesystems and populate them from
206#   our templates.  Support both a direct template and a dir.cpio.gz
207#   archive.  Support dir.remove files containing a list of relative
208#   paths to remove.
209#
210# TODO:
211#   + find a way to assign a 'group' identifier to a machine
212#	so we can use group-specific configurations;
213
214for i in base default ${bootp_ipbca} ${bootp_ipa} ; do
215	for j in /conf/$i/* ; do
216	subdir=${j##*/}
217	if [ -d $j ]; then
218		create_md $subdir
219		cp -Rp $j/* /$subdir
220	fi
221	done
222	for j in /conf/$i/*.cpio.gz ; do
223		subdir=${j%*.cpio.gz}
224		subdir=${subdir##*/}
225		if [ -f $j ]; then
226			create_md $subdir
227			echo "Loading /$subdir from cpio archive $j"
228			(cd / ; /usr/bin/gzip -d < $j | /usr/bin/cpio --extract -d )
229		fi
230	done
231	for j in /conf/$i/*.remove ; do
232		subdir=${j%*.remove}
233		subdir=${subdir##*/}
234		if [ -f $j ]; then
235			# doubly sure it is a memory disk before rm -rf'ing
236			create_md $subdir
237			(cd /$subdir; rm -rf `/bin/cat $j`)
238		fi
239	done
240done
241