rc.initdiskless revision 121066
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: head/etc/rc.initdiskless 121066 2003-10-13 08:18:05Z dougb $ 28# 29# PROVIDE: initdiskless 30# KEYWORD: FreeBSD 31 32 33# On entry to this script the entire system consists of a read-only root 34# mounted via NFS. We use the contents of /conf to create and populate 35# memory filesystems. The kernel has run BOOTP and configured an interface 36# (otherwise it would not have been able to mount the NFS root!) 37# 38# The following directories are scanned. Each sucessive directory overrides 39# (is merged into) the previous one. 40# 41# /conf/base universal base 42# /conf/default modified by a secondary universal base 43# /conf/${ipba} modified based on the assigned broadcast IP 44# /conf/${ip} modified based on the machine's assigned IP 45# 46# Each of these directories may contain any number of subdirectories which 47# represent directories in / on the diskless machine. The existance of 48# these subdirectories causes this script to create a MEMORY FILESYSTEM for 49# /<sub_directory_name>. For example, if /conf/base/etc exists then a 50# memory filesystem will be created for /etc. 51# 52# If a subdirectory contains the file 'diskless_remount' the contents of 53# the file is used to remount the subdirectory prior to it being copied to 54# the memory filesystem. For example, if /conf/base/etc/diskless_remount 55# contains the string 'my.server.com:/etc' then my.server.com:/etc will be 56# mounted in place of the subdirectory. This allows you to avoid making 57# duplicates of system directories in /conf. 58# 59# If a subdirectory contains the file 'md_size', the contents of the 60# file is used to determine the size of the memory filesystem, in 512 61# byte sectors. The default is 10240 (5MB). You only have to specify an 62# md_size if the default doesn't work for you (i.e. if it is too big or 63# too small). For example, /conf/base/etc/md_size might contain '16384'. 64# 65# If /conf/<special_dir>/SUBDIR.cpio.gz exists, the file is cpio'd into 66# the specified /SUBDIR (and a memory filesystem is created for /SUBDIR 67# if necessary). 68# 69# If /conf/<special_dir>/SUBDIR.remove exists, the file contains a list 70# of paths which are rm -rf'd relative to /SUBDIR. 71# 72# You will almost universally want to create a /conf/base/etc containing 73# a diskless_remount and possibly an md_size file. You will then almost 74# universally want to override rc.conf, rc.local, and fstab by creating 75# /conf/default/etc/{rc.conf,rc.local,fstab}. Your fstab should be sure 76# to mount a /usr... typically an NFS readonly /usr. 77# 78# NOTE! /etc/rc.d/diskless will create /var, /tmp, and /dev. 79# Those filesystems should not be specified in /conf. At least not yet. 80 81dlv=`/sbin/sysctl -n vfs.nfs.diskless_valid 2> /dev/null` 82[ ${dlv:=0} -eq 0 ] && exit 0 83 84# chkerr: 85# 86# Routine to check for error 87# 88# checks error code and drops into shell on failure. 89# if shell exits, terminates script as well as /etc/rc. 90# 91chkerr() { 92 case $1 in 93 0) 94 ;; 95 *) 96 echo "$2 failed: dropping into /bin/sh" 97 /bin/sh 98 # RESUME 99 ;; 100 esac 101} 102 103# Create a generic memory disk 104# 105mount_md() { 106 /sbin/mdmfs -i 4096 -s $1 -M md $2 107} 108 109# Create the memory filesystem if it has not already been created 110# 111create_md() { 112 if [ "x`eval echo \\$md_created_$1`" = "x" ]; then 113 if [ "x`eval echo \\$md_size_$1`" = "x" ]; then 114 md_size=10240 115 else 116 md_size=`eval echo \\$md_size_$1` 117 fi 118 mount_md $md_size /$1 119 /bin/chmod 755 /$1 120 eval md_created_$1=created 121 fi 122} 123 124# DEBUGGING 125# 126# set -v 127 128# Figure out our interface and IP. 129# 130bootp_ifc="" 131bootp_ipa="" 132bootp_ipbca="" 133iflist=`ifconfig -l` 134for i in ${iflist} ; do 135 set `ifconfig ${i}` 136 while [ $# -ge 1 ] ; do 137 if [ "${bootp_ifc}" = "" -a "$1" = "inet" ] ; then 138 bootp_ifc=${i} ; bootp_ipa=${2} ; shift 139 fi 140 if [ "${bootp_ipbca}" = "" -a "$1" = "broadcast" ] ; then 141 bootp_ipbca=$2; shift 142 fi 143 shift 144 done 145 if [ "${bootp_ifc}" != "" ] ; then 146 break 147 fi 148done 149echo "Interface ${bootp_ifc} IP-Address ${bootp_ipa} Broadcast ${bootp_ipbca}" 150 151# Figure out our NFS root path 152# 153set `mount -t nfs` 154while [ $# -ge 1 ] ; do 155 if [ "$2" = "on" -a "$3" = "/" ]; then 156 nfsroot="$1" 157 break 158 fi 159 shift 160done 161 162# Resolve templates in /conf/base, /conf/default, /conf/${bootp_ipbca}, 163# and /conf/${bootp_ipa}. For each subdirectory found within these 164# directories: 165# 166# - calculate memory filesystem sizes. If the subdirectory (prior to 167# NFS remounting) contains the file 'md_size', the contents specified 168# in 512 byte sectors will be used to size the memory filesystem. Otherwise 169# 8192 sectors (4MB) is used. 170# 171# - handle NFS remounts. If the subdirectory contains the file 172# diskless_remount, the contents of the file is NFS mounted over 173# the directory. For example /conf/base/etc/diskless_remount 174# might contain 'myserver:/etc'. NFS remounts allow you to avoid 175# having to dup your system directories in /conf. Your server must 176# be sure to export those filesystems -alldirs, however. 177# If the diskless_remount file contains a string beginning with a 178# '/' it is assumed that the local nfsroot should be prepended to 179# it before attemping to the remount. This allows the root to be 180# relocated without needing to change the remount files. 181# 182for i in base default ${bootp_ipbca} ${bootp_ipa} ; do 183 for j in /conf/$i/* ; do 184 # memory filesystem size specification 185 # 186 subdir=${j##*/} 187 if [ -d $j -a -f $j/md_size ]; then 188 eval md_size_$subdir=`cat $j/md_size` 189 fi 190 191 # NFS remount 192 # 193 if [ -d $j -a -f $j/diskless_remount ]; then 194 nfspt=`/bin/cat $j/diskless_remount` 195 if [ `expr "$nfspt" : '\(.\)'` = "/" ]; then 196 nfspt="${nfsroot}${nfspt}" 197 fi 198 mount_nfs $nfspt $j 199 chkerr $? "mount_nfs $nfspt $j" 200 fi 201 done 202done 203 204# - Create all required MFS filesystems and populate them from 205# our templates. Support both a direct template and a dir.cpio.gz 206# archive. Support dir.remove files containing a list of relative 207# paths to remove. 208# 209# TODO: 210# + find a way to assign a 'group' identifier to a machine 211# so we can use group-specific configurations; 212 213for i in base default ${bootp_ipbca} ${bootp_ipa} ; do 214 for j in /conf/$i/* ; do 215 subdir=${j##*/} 216 if [ -d $j ]; then 217 create_md $subdir 218 cp -Rp $j/* /$subdir 219 fi 220 done 221 for j in /conf/$i/*.cpio.gz ; do 222 subdir=${j%*.cpio.gz} 223 subdir=${subdir##*/} 224 if [ -f $j ]; then 225 create_md $subdir 226 echo "Loading /$subdir from cpio archive $j" 227 (cd / ; /stand/gzip -d < $j | /stand/cpio --extract -d ) 228 fi 229 done 230 for j in /conf/$i/*.remove ; do 231 subdir=${j%*.remove} 232 subdir=${subdir##*/} 233 if [ -f $j ]; then 234 # doubly sure it is a memory disk before rm -rf'ing 235 create_md $subdir 236 (cd /$subdir; rm -rf `/bin/cat $j`) 237 fi 238 done 239done 240 241