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 'backup-checkallused'; $? and die $?;
42 setstatus "FAILED reading TAPEID";
43 # Try to read the tape ID from the tape into the file TAPEID
47 setstatus "FAILED during startup";
49 # We need some ID; if the tape has one already that takes precedence;
50 # otherwise the user might have set a tape ID that this should be
51 # by creating really-TAPEID.
52 if (open T, "TAPEID") {
53 unlink 'really-TAPEID';
54 } elsif (open T, "really-TAPEID") {
59 # read the ID; it had better be a non-empty string of alphanumeric chars.
61 $tapeid =~ m/[^0-9a-zA-Z]/ and die "Bad TAPEID ($&).\n";
62 $tapeid =~ m/[0-9a-zA-Z]/ or die "Empty TAPEID.\n";
65 setstatus "FAILED at tape identity check";
67 # We don't let the user overwrite the tape used for the last backup.
68 if (open L, "last-tape") {
69 chomp($lasttape= <L>);
75 die "Tape $tapeid same as last time.\n" if $tapeid eq $lasttape;
77 # $tapeid identifies the individual tape; $tapedesc is its current
78 # identity and function, for printing in messages. You can make these
79 # namespaces the same if you like, or you can make the tape.<tapeid>
80 # files be links to tape.<tapedesc> files.
81 if (defined($tapedesc= readlink "$etc/tape.$tapeid")) {
82 $tapedesc =~ s/^.*\.//;
83 $tapedesc .= "($tapeid)";
88 # Parse the appropriate tape.nn file.
89 # Format is: empty lines and lines starting '#' are ignored. Trailing
90 # whitespace is ignored. File must end with 'end' on a line by itself.
91 # Either there should be a line 'incremental' to indicate that this is
92 # a tape for incremental backups, or a pair of lines 'filesystems fsg'
93 # and 'next tapeid', indicating that this tape is part of a full
94 # backup, containing the filesystem group fsg.
96 open D, "$etc/tape.$tapeid" or die "Unknown tape $tapeid ($!).\n";
98 $_= <D> or die; chomp; s/\s+$//;
102 if (m/^filesystems (\w+)$/) {
104 } elsif (m/^next (\w+)$/) {
106 } elsif (m/^incremental$/) {
109 die "unknown entry in tape $tapeid at line $.: $_\n";
114 # Incremental backups are handled by increm, not us.
116 die "incremental tape $tapeid has next or filesystems\n"
117 if defined($next) || defined($fsys);
118 print STDERR "Incremental tape $tapeid.\n\n";
119 setstatus "FAILED during incremental startup";
120 exec "increm",$tapeid,$tapedesc;
124 # Read the filesystem group definition (file fsys.nnn)
128 $doing= "dump of $fsys to tape $tapedesc in drive $tape";
129 print LOG "$doing:\n" or die $!;
131 setstatus "FAILED retensioning";
132 system "mt -f $tape reten"; $? and die $?;
134 setstatus "FAILED writing tape ID";
135 # First write the tape ID to this tape.
137 writetapeid($tapeid);
139 unlink 'this-md5sums';
141 print "Doing $doing ...\n" or die $!;
144 system 'mknod p p'; $? and die $?;
146 setstatus "FAILED during dump";
149 close(DUMPOR); close(TEEOR); close(BUFOR); close(FINDOR);
150 close(DUMPOW); close(TEEOW); close(BUFOW); close(FINDOW);
153 # work out a find option string that will exclude the required files
154 # Note that dump pays no attention to exclude options.
156 foreach $exc (@excldir) {
157 $exclopt .= "-regex $exc -prune -o ";
159 foreach $exc (@excl) {
160 $exclopt .= "-regex $exc -o ";
163 # For each filesystem to be put on this tape:
166 pipe(FINDOR,FINDOW) or die $!;
167 pipe(DUMPOR,DUMPOW) or die $!;
168 pipe(TEEOR,TEEOW) or die $!;
169 pipe(BUFOR,BUFOW) or die $!;
172 # We can back up via dump or cpio or zafio
174 $dumpcmd= "dump 0bfu $softblocksizekb - $atf";
175 $dumpin= '</dev/null';
176 } elsif ($tm eq 'cpio') {
177 startprocess '</dev/null','>&FINDOW',$rstr."find $atf -xdev -noleaf -print0";
178 $dumpcmd= "cpio -Hustar -o0C$softblocksizebytes";
180 } elsif ($tm eq 'zafio') {
181 # compress-each-file-then-archive using afio
182 startprocess '</dev/null','>&FINDOW',$rstr."find $atf -xdev -noleaf $exclopt -print";
183 # don't use verbose flag as this generates 2MB report emails :->
184 $dumpcmd = "afio -b $softblocksizebytes -Zo -";
185 $dumpin = '<&FINDOR';
187 die "unknown method $tm for $prefix:$atf\n";
189 # This is a funky way of doing a pipeline which pays attention
190 # to the exit status of all the commands in the pipeline.
191 # It is roughly equivalent to:
192 # md5sum <p >>this-md5sums
193 # dump <$dumpin | tee p | writebuffer | dd >/dev/null
194 startprocess '<p','>>this-md5sums','md5sum';
195 startprocess $dumpin,'>&DUMPOW',$rstr.$dumpcmd;
196 startprocess '<&DUMPOR','>&TEEOW','tee p';
197 startprocess '<&TEEOR','>&BUFOW','writebuffer';
198 startprocess '<&BUFOR','>/dev/null'
199 ,"dd ibs=$softblocksizebytes obs=$blocksizebytes of=$ntape";
204 # The backup should now be complete; verify it
206 setstatus "FAILED during check";
208 # Rewind the tape and skip the TAPEID record
209 system "mt -f $tape rewind"; $? and die $?;
210 system "mt -f $ntape fsf 1"; $? and die $?;
212 # Check the md5sums match for each filesystem on the tape
213 open S,"this-md5sums" or die $!;
217 $orgsum =~ m/^[0-9a-fA-F]{32}$/i or die "orgsum \`$orgsum' ?";
218 chomp($csum= `dd if=$ntape ibs=$blocksizebytes | readbuffer | md5sum`);
219 $orgsum eq $csum or die "MISMATCH $tf $csum $orgsum\n";
220 print "checksum ok $csum\t$tf\n" or die $!;
221 print LOG "checksum ok $csum\t$tf\n" or die $!;
224 system "mt -f $tape rewind"; $? and die $?;
226 setstatus "FAILED during cleanup";
228 # Write to some status files to indicate what the backup system
229 # ought to do when next invoked.
230 # reset incremental backup count to 1.
231 open IAN,">increm-advance.new" or die $!;
232 print IAN "1\n" or die $!;
235 # Next full backup is whatever the next link in the tape description
236 # file says it ought to be.
237 open TN,">next-full.new" or die $!;
238 print TN "$next\n" or die $!;
241 unlink 'last-tape','next-full';
242 # We are the last tape to have been backed up
243 rename 'TAPEID','last-tape' or die $!;
244 rename 'this-md5sums',"md5sums.$fsys" or die $!;
245 rename 'log',"log.$fsys" or die $!;
246 rename 'next-full.new',"next-full" or die $!;
247 rename 'increm-advance.new',"increm-advance" or die $!;
249 print "$doing completed.\nNext dump tape is $next.\n" or die $!;
251 setstatus "Successful: $tapedesc $fsys, next $next";