3 # Main backup script - does a full dump or execs increm. Do NOT run directly!
5 # This file is part of chiark backup, a system for backing up GNU/Linux and
6 # other UN*X-compatible machines, as used on chiark.greenend.org.uk.
9 # Copyright (C) 1997-1998,2000-2001 Ian Jackson <ian@chiark.greenend.org.uk>
10 # Copyright (C) 1999 Peter Maydell <pmaydell@chiark.greenend.org.uk>
12 # This is free software; you can redistribute it and/or modify it under the
13 # terms of the GNU General Public License as published by the Free Software
14 # Foundation; either version 2, or (at your option) any later version.
16 # This is distributed in the hope that it will be useful, but WITHOUT ANY
17 # WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
18 # FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
21 # You should have received a copy of the GNU General Public License along
22 # with this program; if not, write to the Free Software Foundation, Inc.,
23 # 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26 $etc= '/etc/chiark-backup';
27 require "$etc/settings.pl";
28 require 'backuplib.pl';
33 # Check to see whether the tape.nn and fsys.nn files are sane.
34 # checkallused checks that all the filesystems mounted are in fact
35 # dumped in both full and incremental dumps.
36 setstatus "FAILED configuration check";
37 print "Configuration check ...\n" or die $!;
38 system 'checkallused'; $? and die $?;
42 setstatus "FAILED reading TAPEID";
43 # Try to read the tape ID from the tape into the file TAPEID
45 system "mt -f $tape rewind"; $? and die $?;
46 system "mt -f $tape setblk $blocksizebytes"; $? and die $?;
47 system "dd if=$tape bs=${blocksize}b count=10 | tar -b$blocksize -vvxf - TAPEID";
49 setstatus "FAILED during startup";
51 # We need some ID; if the tape has one already that takes precedence;
52 # otherwise the user might have set a tape ID that this should be
53 # by creating really-TAPEID.
54 if (open T, "TAPEID") {
55 unlink 'really-TAPEID';
56 } elsif (open T, "really-TAPEID") {
61 # read the ID; it had better be a non-empty string of alphanumeric chars.
63 $tapeid =~ m/[^0-9a-zA-Z]/ and die "Bad TAPEID ($&).\n";
64 $tapeid =~ m/[0-9a-zA-Z]/ or die "Empty TAPEID.\n";
67 setstatus "FAILED at tape identity check";
69 # We don't let the user overwrite the tape used for the last backup.
70 if (open L, "last-tape") {
71 chomp($lasttape= <L>);
77 die "Tape $tapeid same as last time.\n" if $tapeid eq $lasttape;
79 # $tapeid identifies the individual tape; $tapedesc is its current
80 # identity and function, for printing in messages. You can make these
81 # namespaces the same if you like, or you can make the tape.<tapeid>
82 # files be links to tape.<tapedesc> files.
83 if (defined($tapedesc= readlink "$etc/tape.$tapeid")) {
84 $tapedesc =~ s/^.*\.//;
85 $tapedesc .= "($tapeid)";
90 # Parse the appropriate tape.nn file.
91 # Format is: empty lines and lines starting '#' are ignored. Trailing
92 # whitespace is ignored. File must end with 'end' on a line by itself.
93 # Either there should be a line 'incremental' to indicate that this is
94 # a tape for incremental backups, or a pair of lines 'filesystems fsg'
95 # and 'next tapeid', indicating that this tape is part of a full
96 # backup, containing the filesystem group fsg.
98 open D, "$etc/tape.$tapeid" or die "Unknown tape $tapeid ($!).\n";
100 $_= <D> or die; chomp; s/\s+$//;
104 if (m/^filesystems (\w+)$/) {
106 } elsif (m/^next (\w+)$/) {
108 } elsif (m/^incremental$/) {
111 die "unknown entry in tape $tapeid at line $.: $_\n";
116 # Incremental backups are handled by increm, not us.
118 die "incremental tape $tapeid has next or filesystems\n"
119 if defined($next) || defined($fsys);
120 print STDERR "Incremental tape $tapeid.\n\n";
121 setstatus "FAILED during incremental startup";
122 exec "increm",$tapeid,$tapedesc;
126 # Read the filesystem group definition (file fsys.nnn)
130 $doing= "dump of $fsys to tape $tapedesc in drive $tape";
131 print LOG "$doing:\n" or die $!;
133 setstatus "FAILED writing tape ID";
134 # First write the tape ID to this tape.
135 open T, ">TAPEID" or die $!;
136 print T "$tapeid\n" or die $!;
139 system "tar -b$blocksize -vvcf TAPEID.tar TAPEID"; $? and die $?;
140 system "dd if=TAPEID.tar of=$ntape bs=${blocksize}b count=10"; $? and die $?;
142 unlink 'this-md5sums';
144 print "Doing $doing ...\n" or die $!;
147 system 'mknod p p'; $? and die $?;
149 setstatus "FAILED during dump";
152 close(DUMPOR); close(TEEOR); close(BUFOR); close(FINDOR);
153 close(DUMPOW); close(TEEOW); close(BUFOW); close(FINDOW);
156 # work out a find option string that will exclude the required files
157 # Note that dump pays no attention to exclude options.
159 foreach $exc (@excldir) {
160 $exclopt .= "-regex $exc -prune -o ";
162 foreach $exc (@excl) {
163 $exclopt .= "-regex $exc -o ";
166 # For each filesystem to be put on this tape:
169 pipe(FINDOR,FINDOW) or die $!;
170 pipe(DUMPOR,DUMPOW) or die $!;
171 pipe(TEEOR,TEEOW) or die $!;
172 pipe(BUFOR,BUFOW) or die $!;
175 # We can back up via dump or cpio or zafio
177 $dumpcmd= "dump 0bfu $softblocksizekb - $atf";
178 $dumpin= '</dev/null';
179 } elsif ($tm eq 'cpio') {
180 startprocess '</dev/null','>&FINDOW',$rstr."find $atf -xdev -noleaf -print0";
181 $dumpcmd= "cpio -Hustar -o0C$softblocksizebytes";
183 } elsif ($tm eq 'zafio') {
184 # compress-each-file-then-archive using afio
185 startprocess '</dev/null','>&FINDOW',$rstr."find $atf -xdev -noleaf $exclopt -print";
186 # don't use verbose flag as this generates 2MB report emails :->
187 $dumpcmd = "afio -b $softblocksizebytes -Zo -";
188 $dumpin = '<&FINDOR';
190 die "unknown method $tm for $prefix:$atf\n";
192 # This is a funky way of doing a pipeline which pays attention
193 # to the exit status of all the commands in the pipeline.
194 # It is roughly equivalent to:
195 # md5sum <p >>this-md5sums
196 # dump <$dumpin | tee p | writebuffer | dd >/dev/null
197 startprocess '<p','>>this-md5sums','md5sum';
198 startprocess $dumpin,'>&DUMPOW',$rstr.$dumpcmd;
199 startprocess '<&DUMPOR','>&TEEOW','tee p';
200 startprocess '<&TEEOR','>&BUFOW','writebuffer';
201 startprocess '<&BUFOR','>/dev/null'
202 ,"dd ibs=$softblocksizebytes obs=$blocksizebytes of=$ntape";
207 # The backup should now be complete; verify it
209 setstatus "FAILED during check";
211 # Rewind the tape and skip the TAPEID record
212 system "mt -f $tape rewind"; $? and die $?;
213 system "mt -f $ntape fsf 1"; $? and die $?;
215 # Check the md5sums match for each filesystem on the tape
216 open S,"this-md5sums" or die $!;
220 $orgsum =~ m/^[0-9a-fA-F]{32}$/i or die "orgsum \`$orgsum' ?";
221 chomp($csum= `dd if=$ntape ibs=$blocksizebytes | readbuffer | md5sum`);
222 $orgsum eq $csum or die "MISMATCH $tf $csum $orgsum\n";
223 print "checksum ok $csum\t$tf\n" or die $!;
224 print LOG "checksum ok $csum\t$tf\n" or die $!;
227 system "mt -f $tape rewind"; $? and die $?;
229 setstatus "FAILED during cleanup";
231 # Write to some status files to indicate what the backup system
232 # ought to do when next invoked.
233 # reset incremental backup count to 1.
234 open IAN,">increm-advance.new" or die $!;
235 print IAN "1\n" or die $!;
238 # Next full backup is whatever the next link in the tape description
239 # file says it ought to be.
240 open TN,">next-full.new" or die $!;
241 print TN "$next\n" or die $!;
244 unlink 'last-tape','next-full';
245 # We are the last tape to have been backed up
246 rename 'TAPEID','last-tape' or die $!;
247 rename 'this-md5sums',"md5sums.$fsys" or die $!;
248 rename 'log',"log.$fsys" or die $!;
249 rename 'next-full.new',"next-full" or die $!;
250 rename 'increm-advance.new',"increm-advance" or die $!;
252 print "$doing completed.\nNext dump tape is $next.\n" or die $!;
254 setstatus "Successful: $tapedesc $fsys, next $next";