backupninja/handlers/maildir
Elijah Saxon 995e34e166 created function maketemp, to be used by backupninja
and maildir handler for creating safe temp files.
2005-10-02 12:45:12 +00:00

309 lines
8.7 KiB
Plaintext

###############################################################
#
# This handler slowly creates a backup of each user's maildir
# to a remote server. It is designed to be run with low overhead
# in terms of cpu and bandwidth so it runs pretty slow.
#
# if destdir is /backup/maildir/, then it will contain the files
# daily.1
# daily.2
# daily.3
# weekly.1
# weekly.2
# monthly.1
# if keepdaily is 3, keepweekly is 2, and keepmonthly is 1.
#
# The basic algorithm is to rsync each maildir individually,
# and to use hard links for retaining historical data.
#
# We rsync each maildir individually because it becomes very
# unweldy to start a single rsync of many hundreds of thousands
# of files.
#
# For the backup rotation to work, destuser must be able to run
# arbitrary bash commands on the desthost.
#
##############################################################
getconf rotate yes
getconf remove yes
getconf loadlimit 5
getconf speedlimit 0
getconf keepdaily 5
getconf keepweekly 3
getconf keepmonthly 1
getconf srcdir /var/maildir
getconf destdir
getconf desthost
getconf destport 22
getconf destuser
failedcount=0
# strip trailing /
destdir=${destdir%/}
srcdir=${srcdir%/}
# used for testing
#getconf letter
#getconf testuser elijah
getconf backup yes
#letters=e
letters="a b c d e f g h i j k l m n o p q r s t u v w x y z"
[ -d $srcdir ] || fatal "source directory $srcdir doesn't exist"
[ ! $test ] || testflags="--dry-run -v"
rsyncflags="$testflags -e 'ssh -p $destport' -r -v --ignore-existing --delete --size-only --bwlimit=$speedlimit"
excludes="--exclude '.Trash/\*' --exclude '.Mistakes/\*' --exclude '.Spam/\*'"
# see if we can login
debug "ssh -o PasswordAuthentication=no $desthost -l $destuser 'echo -n 1'"
if [ ! $test ]; then
result=`ssh -o PasswordAuthentication=no $desthost -l $destuser 'echo -n 1' 2>&1`
if [ "$result" != "1" ]; then
fatal "Can't connect to $desthost as $destuser."
fi
fi
##################################################################
### FUNCTIONS
function do_user() {
local user=$1
local destdir=$2
local letter=${user:0:1}
local dir="$srcdir/$letter/$user"
[ -d $dir ] || fatal "maildir $dir not found".
# while true; do
# load=`uptime | sed 's/^.*load average: \\([^,]*\\).*$/\\1/'`
# over=`expr $load \> $loadlimit`
# if [ $over == 1 ]; then
# info "load $load, sleeping..."
# sleep 600
# else
# break
# fi
# done
cmd="$RSYNC $rsyncflags $excludes $dir $destuser@$desthost:$destdir/$letter"
ret=`rsync -e "ssh -p $destport" -r \
--links --ignore-existing --delete --size-only --bwlimit=$speedlimit \
--exclude '.Trash/*' --exclude '.Mistakes/*' --exclude '.Spam/*' \
$dir $destuser@$desthost:$destdir/$letter \
2>&1`
ret=$?
# ignore 0 (success) and 24 (file vanished before it could be copied)
if [ $ret != 0 -a $ret != 24 ]; then
warning "rsync $user failed"
warning " returned: $ret"
let "failedcount = failedcount + 1"
if [ $failedcount -gt 100 ]; then
fatal "100 rsync errors -- something is not working right. bailing out."
fi
fi
}
# remove any maildirs from backup which might have been deleted
# and add new ones which have just been created.
function do_remove() {
local tmp1=`maketemp maildir-tmp-file`
local tmp2=`maketemp maildir-tmp-file`
for i in a b c d e f g h i j k l m n o p q r s t u v w x y z; do
ls -1 "$srcdir/$i" | sort > $tmp1
ssh -p $destport $desthost ls -1 '$destdir/maildir/$i' | sort > $tmp2
for deluser in `join -v 2 $tmp1 $tmp2`; do
cmd="ssh -p $destport $desthost rm -vr '$destdir/maildir/$i/$deluser/'"
debug $cmd
done
done
rm $tmp1
rm $tmp2
}
function do_rotate() {
backuproot=$destdir
(
debug Connecting to $desthost
ssh -T -o PasswordAuthentication=no $desthost -l $destuser <<EOF
##### BEGIN REMOTE SCRIPT #####
seconds_daily=86400
seconds_weekly=604800
seconds_monthly=2628000
keepdaily=$keepdaily
keepweekly=$keepweekly
keepmonthly=$keepmonthly
now=\`date +%s\`
for rottype in daily weekly monthly; do
seconds=\$((seconds_\${rottype}))
dir="$backuproot/\$rottype"
if [ ! -d \$dir.1 ]; then
echo "Info: \$dir.1 does not exist. This backup is missing, so we are skipping the rotation."
continue 1
elif [ ! -f \$dir.1/created ]; then
echo "Warning: \$dir.1/created does not exist. This backup may be only partially completed. Skipping rotation."
continue 1
fi
# Rotate the current list of backups, if we can.
oldest=\`find $backuproot -type d -maxdepth 1 -name \$rottype'.*' | sed 's/^.*\.//' | sort -n | tail -1\`
echo "Debug: oldest \$oldest"
[ "\$oldest" == "" ] && oldest=0
for (( i=\$oldest; i > 0; i-- )); do
if [ -d \$dir.\$i ]; then
if [ -f \$dir.\$i/created ]; then
created=\`tail -1 \$dir.\$i/created\`
else
created=0
fi
cutoff_time=\$(( now - (seconds*(i-1)) ))
if [ ! \$created -gt \$cutoff_time ]; then
next=\$(( i + 1 ))
if [ ! -d \$dir.\$next ]; then
echo "Debug: mv \$dir.\$i \$dir.\$next"
mv \$dir.\$i \$dir.\$next
date +%c%n%s > \$dir.\$next/rotated
else
echo "Info: skipping rotation of \$dir.\$i because \$dir.\$next already exists."
fi
else
echo "Info: skipping rotation of \$dir.\$i because it was created" \$(( (now-created)/86400)) "days ago ("\$(( (now-cutoff_time)/86400))" needed)."
fi
fi
done
done
max=\$((keepdaily+1))
if [ \( \$keepweekly -gt 0 -a -d $backuproot/daily.\$max \) -a ! -d $backuproot/weekly.1 ]; then
echo mv $backuproot/daily.\$max $backuproot/weekly.1
mv $backuproot/daily.\$max $backuproot/weekly.1
date +%c%n%s > $backuproot/weekly.1/rotated
fi
max=\$((keepweekly+1))
if [ \( \$keepmonthly -gt 0 -a -d $backuproot/weekly.\$max \) -a ! -d $backuproot/monthly.1 ]; then
echo mv $backuproot/weekly.\$max $backuproot/monthly.1
mv $backuproot/weekly.\$max $backuproot/monthly.1
date +%c%n%s > $backuproot/monthly.1/rotated
fi
for rottype in daily weekly monthly; do
max=\$((keep\${rottype}+1))
dir="$backuproot/\$rottype"
oldest=\`find $backuproot -type d -maxdepth 1 -name \$rottype'.*' | sed 's/^.*\.//' | sort -n | tail -1\`
[ "\$oldest" == "" ] && oldest=0
# if we've rotated the last backup off the stack, remove it.
for (( i=\$oldest; i >= \$max; i-- )); do
if [ -d \$dir.\$i ]; then
if [ -d $backuproot/rotate.tmp ]; then
echo "Info: removing $backuproot/rotate.tmp"
rm -rf $backuproot/rotate.tmp
fi
echo "Info: moving \$dir.\$i to $backuproot/rotate.tmp"
mv \$dir.\$i $backuproot/rotate.tmp
fi
done
done
####### END REMOTE SCRIPT #######
EOF
) | (while read a; do passthru $a; done)
}
function setup_remote_dirs() {
local backuptype=$1
local dir="$destdir/$backuptype"
(
ssh -T -o PasswordAuthentication=no $desthost -l $destuser <<EOF
if [ ! -d $destdir ]; then
echo "Fatal: Destination directory $destdir does not exist on host $desthost."
exit 1
elif [ -d $dir.1 ]; then
if [ -f $dir.1/created ]; then
echo "Warning: $dir.1 already exists. Overwriting contents."
else
echo "Warning: we seem to be resuming a partially written $dir.1"
fi
else
if [ -d $destdir/rotate.tmp ]; then
mv $destdir/rotate.tmp $dir.1
if [ \$? == 1 ]; then
echo "Fatal: could mv $destdir/rotate.tmp $dir.1 on host $desthost"
exit 1
fi
else
mkdir $dir.1
if [ \$? == 1 ]; then
echo "Fatal: could not create directory $dir.1 on host $desthost"
exit 1
fi
for i in a b c d e f g h i j k l m n o p q r s t u v w y x z; do
mkdir $dir.1/\$i
done
fi
if [ -d $destdir/$backuptype.2 ]; then
echo "Info: updating hard links to $dir.1. This may take a while."
cp -alf $destdir/$backuptype.2/. $dir.1
#if [ \$? == 1 ]; then
# echo "Fatal: could not create hard links to $dir.1 on host $desthost"
# exit 1
#fi
fi
fi
[ -f $dir.1/created ] && rm $dir.1/created
[ -f $dir.1/rotated ] && rm $dir.1/rotated
exit 0
EOF
) | (while read a; do passthru $a; done)
if [ $? == 1 ]; then exit; fi
}
###
##################################################################
### ROTATE BACKUPS ###
if [ "$rotate" == "yes" ]; then
do_rotate
fi
### REMOVE OLD MAILDIRS ###
if [ "$remove" == "yes" ]; then
debug remove
fi
### MAKE BACKUPS ###
if [ "$backup" == "yes" ]; then
if [ $keepdaily -gt 0 ]; then btype=daily
elif [ $keepweekly -gt 0 ]; then btype=weekly
elif [ $keepmonthly -gt 0 ]; then btype=monthly
else fatal "keeping no backups"; fi
setup_remote_dirs $btype
for i in $letters; do
[ -d "$srcdir/$i" ] || fatal "directory $srcdir/$i not found."
cd "$srcdir/$i"
debug $i
for user in `ls -1`; do
if [ "$testuser" != "" -a "$testuser" != "$user" ]; then continue; fi
do_user $user $destdir/$btype.1
done
done
ssh -o PasswordAuthentication=no $desthost -l $destuser "date +%c%n%s > $destdir/$btype.1/created"
fi