3 # Copyright (c) 1999 Matt Dillon
6 # Redistribution and use in source and binary forms, with or without
7 # modification, are permitted provided that the following conditions
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.
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
29 # On entry to this script the entire system consists of a read-only root
30 # mounted via NFS. The kernel has run BOOTP and configured an interface
31 # (otherwise it would not have been able to mount the NFS root!)
33 # We use the contents of /conf to create and populate memory filesystems
34 # that are mounted on top of this root to implement the writable
35 # (and host-specific) parts of the root filesystem, and other volatile
38 # The hierarchy in /conf has the form /conf/T/M/ where M are directories
39 # for which memory filesystems will be created and filled,
40 # and T is one of the "template" directories below:
42 # base universal base, typically a replica of the original root;
43 # default secondary universal base, typically overriding some
44 # of the files in the original root;
45 # ${ipba} where ${ipba} is the assigned broadcast IP address
46 # ${class} where ${class} is a list of directories supplied by
47 # bootp/dhcp through the T134 option.
48 # ${ipba} and ${class} are typicall used to configure features
49 # for group of diskless clients, or even individual features;
50 # ${ip} where ${ip} is the machine's assigned IP address, typically
51 # used to set host-specific features;
53 # Template directories are scanned in the order they are listed above,
54 # with each sucessive directory overriding (merged into) the previous one;
55 # non-existing directories are ignored.
57 # The existence of a directory /conf/T/M causes this script to create a
58 # memory filesystem mounted as /M on the client.
60 # Some files in /conf have special meaning, namely:
63 # ----------------------------------------------------------------
65 # The contents of the file is a mount command. E.g. if
66 # /conf/1.2.3.4/foo/remount contains "mount -o ro /dev/ad0s3",
67 # then /dev/ad0s3 will be be mounted on /conf/1.2.3.4/foo/
69 # /conf/T/M/diskless_remount
70 # The contents of the file points to an NFS filesystem. E.g. if
71 # /conf/base/etc/diskless_remount contains "foo.com:/etc",
72 # then foo.com:/etc will be be mounted on /conf/base/etc/
73 # If the file contains a pathname starting with "/", then
74 # the root path is prepended to it; this allows relocation of
75 # the root filesystem withouth changing configuration files.
78 # The contents of the file specifies the size of the memory
79 # filesystem to be created, in 512 byte blocks.
80 # The default size is 10240 blocks (5MB). E.g. if
81 # /conf/base/etc/md_size contains "30000" then a 15MB MFS
82 # will be created. In case of multiple entries for the same
83 # directory M, the last one in the scanning order is used.
84 # NOTE: If you only need to create a memory filesystem but not
85 # initialize it from a template, it is preferrable to specify
86 # it in fstab e.g. as "md /tmp mfs -s=30m,rw 0 0"
88 # /conf/T/SUBDIR.cpio.gz
89 # The file is cpio'd into /SUBDIR (and a memory filesystem is
90 # created for /SUBDIR if necessary). The presence of this file
91 # prevents the copy from /conf/T/SUBDIR/
93 # /conf/T/SUBDIR.remove
94 # The list of paths contained in the file are rm -rf'd
95 # relative to /SUBDIR.
97 # You will almost universally want to create the following files under /conf
100 # ---------------------------- ------------------------------------------
101 # /conf/base/etc/md_size size of /etc filesystem
102 # /conf/base/diskless_remount "/etc"
103 # /conf/default/etc/rc.conf generic diskless config parameters
104 # /conf/default/etc/fstab generic diskless fstab e.g. like this
106 # foo:/root_part / nfs ro 0 0
107 # foo:/usr_part /usr nfs ro 0 0
108 # foo:/home_part /home nfs rw 0 0
109 # md /tmp mfs -s=30m,rw 0 0
110 # md /var mfs -s=30m,rw 0 0
111 # proc /proc procfs rw 0 0
113 # plus, possibly, overrides for password files etc.
115 # NOTE! /var, /tmp, and /dev will be typically created elsewhere, e.g.
116 # as entries in the fstab as above.
117 # Those filesystems should not be specified in /conf.
119 # (end of documentation, now get to the real code)
121 dlv=`/sbin/sysctl -n vfs.nfs.diskless_valid 2> /dev/null`
125 # Routine to check for error
127 # checks error code and drops into shell on failure.
128 # if shell exits, terminates script as well as /etc/rc.
135 echo "$2 failed: dropping into /bin/sh"
142 # Create a generic memory disk
145 /sbin/mdmfs -i 4096 -s $1 -M md $2
148 # Create the memory filesystem if it has not already been created
151 if [ "x`eval echo \\$md_created_$1`" = "x" ]; then
152 if [ "x`eval echo \\$md_size_$1`" = "x" ]; then
155 md_size=`eval echo \\$md_size_$1`
157 mount_md $md_size /$1
159 eval md_created_$1=created
167 # Figure out our interface and IP.
172 if [ ${dlv:=0} -ne 0 ] ; then
174 for i in ${iflist} ; do
175 set -- `ifconfig ${i}`
176 while [ $# -ge 1 ] ; do
177 if [ "${bootp_ifc}" = "" -a "$1" = "inet" ] ; then
178 bootp_ifc=${i} ; bootp_ipa=${2} ; shift
180 if [ "${bootp_ipbca}" = "" -a "$1" = "broadcast" ] ; then
181 bootp_ipbca=$2; shift
185 if [ "${bootp_ifc}" != "" ] ; then
189 # Insert the directories passed with the T134 bootp cookie
190 # in the list of paths used for templates.
191 i="`/sbin/sysctl -n kern.bootp_cookie`"
192 [ "${i}" != "" ] && bootp_ipbca="${bootp_ipbca} ${i}"
194 echo "Interface ${bootp_ifc} IP-Address ${bootp_ipa} Broadcast ${bootp_ipbca}"
197 # Figure out our NFS root path
199 set -- `mount -t nfs`
200 while [ $# -ge 1 ] ; do
201 if [ "$2" = "on" -a "$3" = "/" ]; then
208 # The list of directories with template files
209 templates="base default ${bootp_ipbca} ${bootp_ipa}"
211 # The list of filesystems to umount after the copy
214 # If /conf/diskless_remount exists, remount all of /conf. This allows
215 # multiple roots to share the same conf files.
216 if [ -d /conf -a -f /conf/diskless_remount ]; then
217 nfspt=`/bin/cat /conf/diskless_remount`
218 if [ `expr "$nfspt" : '\(.\)'` = "/" ]; then
219 nfspt="${nfsroot}${nfspt}"
221 mount_nfs $nfspt /conf
222 chkerr $? "mount_nfs $nfspt /conf"
226 # Resolve templates in /conf/base, /conf/default, /conf/${bootp_ipbca},
227 # and /conf/${bootp_ipa}. For each subdirectory found within these
230 # - calculate memory filesystem sizes. If the subdirectory (prior to
231 # NFS remounting) contains the file 'md_size', the contents specified
232 # in 512 byte sectors will be used to size the memory filesystem. Otherwise
233 # 8192 sectors (4MB) is used.
235 # - handle NFS remounts. If the subdirectory contains the file
236 # diskless_remount, the contents of the file is NFS mounted over
237 # the directory. For example /conf/base/etc/diskless_remount
238 # might contain 'myserver:/etc'. NFS remounts allow you to avoid
239 # having to dup your system directories in /conf. Your server must
240 # be sure to export those filesystems -alldirs, however.
241 # If the diskless_remount file contains a string beginning with a
242 # '/' it is assumed that the local nfsroot should be prepended to
243 # it before attemping to the remount. This allows the root to be
244 # relocated without needing to change the remount files.
246 for i in ${templates} ; do
247 for j in /conf/$i/* ; do
248 # memory filesystem size specification
251 if [ -d $j -a -f $j/md_size ]; then
252 eval md_size_$subdir=`cat $j/md_size`
257 if [ -d $j -a -f $j/remount ]; then
258 nfspt=`/bin/cat $j/remount`
260 chkerr $? "$nfspt $j"
261 to_umount="${to_umount} $j" # XXX hope it is really a mount!
266 if [ -d $j -a -f $j/diskless_remount ]; then
267 nfspt=`/bin/cat $j/diskless_remount`
268 if [ `expr "$nfspt" : '\(.\)'` = "/" ]; then
269 nfspt="${nfsroot}${nfspt}"
272 chkerr $? "mount_nfs $nfspt $j"
273 to_umount="${to_umount} $j"
278 # - Create all required MFS filesystems and populate them from
279 # our templates. Support both a direct template and a dir.cpio.gz
280 # archive. Support dir.remove files containing a list of relative
283 # The dir.cpio.gz form is there to make the copy process more efficient,
284 # so if the cpio archive is present, it prevents the files from dir/
287 for i in ${templates} ; do
288 for j in /conf/$i/* ; do
290 if [ -d $j -a ! -f $j.cpio.gz ]; then
295 for j in /conf/$i/*.cpio.gz ; do
296 subdir=${j%*.cpio.gz}
300 echo "Loading /$subdir from cpio archive $j"
301 (cd / ; /rescue/pax -x cpio -r -z -p e -f $j)
304 for j in /conf/$i/*.remove ; do
308 # doubly sure it is a memory disk before rm -rf'ing
310 (cd /$subdir; rm -rf `/bin/cat $j`)
315 # umount partitions used to fill the memory filesystems
316 [ -n "${to_umount}" ] && umount $to_umount