X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=chiark-utils.git;a=blobdiff_plain;f=backup%2Ffull;h=02b5b0c60d89b41ba85a068335cf1e59af39dd5f;hp=d3efa171894b752bb047f55049af0b6a47c3f7bb;hb=17fb3a3831ca812a3ad384f4eec3b977432facd9;hpb=3f7f507605d77ece782e847a5a1606197268f220 diff --git a/backup/full b/backup/full index d3efa17..02b5b0c 100755 --- a/backup/full +++ b/backup/full @@ -1,24 +1,56 @@ #!/usr/bin/perl +# full +# Main backup script - does a full dump or execs increm. Do NOT run directly! +# +# This file is part of chiark backup, a system for backing up GNU/Linux and +# other UN*X-compatible machines, as used on chiark.greenend.org.uk. +# +# chiark backup is: +# Copyright (C) 1997-1998,2000-2001 Ian Jackson +# Copyright (C) 1999 Peter Maydell +# +# This is free software; you can redistribute it and/or modify it under the +# terms of the GNU General Public License as published by the Free Software +# Foundation; either version 2, or (at your option) any later version. +# +# This is distributed in the hope that it will be useful, but WITHOUT ANY +# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more +# details. +# +# You should have received a copy of the GNU General Public License along +# with this program; if not, write to the Free Software Foundation, Inc., +# 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. BEGIN { - $etc= '/etc/backup'; + $etc= '/etc/chiark-backup'; require "$etc/settings.pl"; require 'backuplib.pl'; } $|=1; +# Check to see whether the tape.nn and fsys.nn files are sane. +# checkallused checks that all the filesystems mounted are in fact +# dumped in both full and incremental dumps. +setstatus "FAILED configuration check"; print "Configuration check ...\n" or die $!; -system 'checkallused'; $? and die $?; +system 'backup-checkallused'; $? and die $?; printdate(); +setstatus "FAILED reading TAPEID"; +# Try to read the tape ID from the tape into the file TAPEID unlink 'TAPEID'; +system "mt -f $tape rewind"; $? and die $?; system "mt -f $tape setblk $blocksizebytes"; $? and die $?; system "dd if=$tape bs=${blocksize}b count=10 | tar -b$blocksize -vvxf - TAPEID"; setstatus "FAILED during startup"; +# We need some ID; if the tape has one already that takes precedence; +# otherwise the user might have set a tape ID that this should be +# by creating really-TAPEID. if (open T, "TAPEID") { unlink 'really-TAPEID'; } elsif (open T, "really-TAPEID") { @@ -26,6 +58,7 @@ if (open T, "TAPEID") { die "No TAPEID.\n"; } +# read the ID; it had better be a non-empty string of alphanumeric chars. chomp($tapeid= ); $tapeid =~ m/[^0-9a-zA-Z]/ and die "Bad TAPEID ($&).\n"; $tapeid =~ m/[0-9a-zA-Z]/ or die "Empty TAPEID.\n"; @@ -33,6 +66,7 @@ close T; setstatus "FAILED at tape identity check"; +# We don't let the user overwrite the tape used for the last backup. if (open L, "last-tape") { chomp($lasttape= ); close L; @@ -42,6 +76,24 @@ if (open L, "last-tape") { die "Tape $tapeid same as last time.\n" if $tapeid eq $lasttape; +# $tapeid identifies the individual tape; $tapedesc is its current +# identity and function, for printing in messages. You can make these +# namespaces the same if you like, or you can make the tape. +# files be links to tape. files. +if (defined($tapedesc= readlink "$etc/tape.$tapeid")) { + $tapedesc =~ s/^.*\.//; + $tapedesc .= "($tapeid)"; +} else { + $tapedesc = $tapeid; +} + +# Parse the appropriate tape.nn file. +# Format is: empty lines and lines starting '#' are ignored. Trailing +# whitespace is ignored. File must end with 'end' on a line by itself. +# Either there should be a line 'incremental' to indicate that this is +# a tape for incremental backups, or a pair of lines 'filesystems fsg' +# and 'next tapeid', indicating that this tape is part of a full +# backup, containing the filesystem group fsg. undef $fsys; open D, "$etc/tape.$tapeid" or die "Unknown tape $tapeid ($!).\n"; for (;;) { @@ -61,24 +113,25 @@ for (;;) { } close D or die $!; +# Incremental backups are handled by increm, not us. if ($incremental) { die "incremental tape $tapeid has next or filesystems\n" if defined($next) || defined($fsys); print STDERR "Incremental tape $tapeid.\n\n"; setstatus "FAILED during incremental startup"; - exec "increm $tapeid"; + exec "increm",$tapeid,$tapedesc; die $!; } +# Read the filesystem group definition (file fsys.nnn) readfsys("$fsys"); openlog(); -$doing= "dump of $fsys to tape $tapeid in drive $tape"; +$doing= "dump of $fsys to tape $tapedesc in drive $tape"; print LOG "$doing:\n" or die $!; -system "mt -f $tape rewind"; $? and die $?; -system "mt -f $tape retension"; $? and die $?; - +setstatus "FAILED writing tape ID"; +# First write the tape ID to this tape. open T, ">TAPEID" or die $!; print T "$tapeid\n" or die $!; close T or die $!; @@ -100,6 +153,17 @@ sub closepipes () { close(DUMPOW); close(TEEOW); close(BUFOW); close(FINDOW); } +# work out a find option string that will exclude the required files +# Note that dump pays no attention to exclude options. +$exclopt = ''; +foreach $exc (@excldir) { + $exclopt .= "-regex $exc -prune -o "; +} +foreach $exc (@excl) { + $exclopt .= "-regex $exc -o "; +} + +# For each filesystem to be put on this tape: for $tf (@fsys) { printdate(); pipe(FINDOR,FINDOW) or die $!; @@ -107,14 +171,29 @@ for $tf (@fsys) { pipe(TEEOR,TEEOW) or die $!; pipe(BUFOR,BUFOW) or die $!; parsefsys(); + + # We can back up via dump or cpio or zafio if ($tm eq 'dump') { $dumpcmd= "dump 0bfu $softblocksizekb - $atf"; $dumpin= '&FINDOW',$rstr."find $atf -xdev -noleaf -print0"; $dumpcmd= "cpio -Hustar -o0C$softblocksizebytes"; $dumpin= '<&FINDOR'; + } elsif ($tm eq 'zafio') { + # compress-each-file-then-archive using afio + startprocess '&FINDOW',$rstr."find $atf -xdev -noleaf $exclopt -print"; + # don't use verbose flag as this generates 2MB report emails :-> + $dumpcmd = "afio -b $softblocksizebytes -Zo -"; + $dumpin = '<&FINDOR'; + } else { + die "unknown method $tm for $prefix:$atf\n"; } + # This is a funky way of doing a pipeline which pays attention + # to the exit status of all the commands in the pipeline. + # It is roughly equivalent to: + # md5sum

>this-md5sums + # dump <$dumpin | tee p | writebuffer | dd >/dev/null startprocess '>this-md5sums','md5sum'; startprocess $dumpin,'>&DUMPOW',$rstr.$dumpcmd; startprocess '<&DUMPOR','>&TEEOW','tee p'; @@ -125,17 +204,21 @@ for $tf (@fsys) { endprocesses(); } +# The backup should now be complete; verify it + setstatus "FAILED during check"; +# Rewind the tape and skip the TAPEID record system "mt -f $tape rewind"; $? and die $?; system "mt -f $ntape fsf 1"; $? and die $?; +# Check the md5sums match for each filesystem on the tape open S,"this-md5sums" or die $!; for $tf (@fsys) { printdate(); chomp($orgsum= ); $orgsum =~ m/^[0-9a-fA-F]{32}$/i or die "orgsum \`$orgsum' ?"; - chomp($csum= `readbuffer <$ntape | md5sum`); + chomp($csum= `dd if=$ntape ibs=$blocksizebytes | readbuffer | md5sum`); $orgsum eq $csum or die "MISMATCH $tf $csum $orgsum\n"; print "checksum ok $csum\t$tf\n" or die $!; print LOG "checksum ok $csum\t$tf\n" or die $!; @@ -145,15 +228,21 @@ system "mt -f $tape rewind"; $? and die $?; setstatus "FAILED during cleanup"; +# Write to some status files to indicate what the backup system +# ought to do when next invoked. +# reset incremental backup count to 1. open IAN,">increm-advance.new" or die $!; print IAN "1\n" or die $!; close IAN or die $!; +# Next full backup is whatever the next link in the tape description +# file says it ought to be. open TN,">next-full.new" or die $!; print TN "$next\n" or die $!; close TN or die $!; unlink 'last-tape','next-full'; +# We are the last tape to have been backed up rename 'TAPEID','last-tape' or die $!; rename 'this-md5sums',"md5sums.$fsys" or die $!; rename 'log',"log.$fsys" or die $!; @@ -162,5 +251,5 @@ rename 'increm-advance.new',"increm-advance" or die $!; print "$doing completed.\nNext dump tape is $next.\n" or die $!; -setstatus "Successful ($tapeid $fsys, next $next)"; +setstatus "Successful: $tapedesc $fsys, next $next"; exit 0;