backupninja/handlers/dsync.in
Micah Anderson 41c3544ed5 dsync: the dsync handler incorrectly would test for >3 failures before
emitting the failure message, it should do so at =>3
2015-03-30 12:23:50 -04:00

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# -*- mode: sh; sh-basic-offset: 3; indent-tabs-mode: nil; -*-
# vim: set filetype=sh sw=3 sts=3 expandtab autoindent:
###############################################################
#
# This handler uses dovecot (version 2 or later) dsync backup
# to backup mail to a remote server.
#
# Source and destination directories are typically configured
# via the dovecot configuration, but can be overridden using
# the settings here.
#
# if the configuration is setup to have keepdaily at 3,
# keepweekly is 2, and keepmonthly is 1, then each user's
# maildir backup snapshot directory will contain these files:
# daily.1
# daily.2
# daily.3
# weekly.1
# weekly.2
# monthly.1
#
# The basic algorithm is to dsync each user individually,
# and to use hard links for retaining historical data.
#
# For the backup rotation to work, destuser must be able to run
# arbitrary bash commands on the desthost.
#
# If 'remove' is set to 'yes' (default), then any mail directory
# which is deleted from the source will be moved to a "deleted"
# directory in the destination. It is up to you to periodically
# remove this directory or old maildirs in it.
#
# Limitations:
# . because we are not dynamically looking up anything with
# dovecot's userdb, we expect all data to be under the same
# tree on both the source and destination
#
# . we are assuming a backup to a backup server, so the
# destination host should have its dovecot mail_location
# configured to put the mail into
# $stripped_destdir/$letter/$user/$current_backup
#
##############################################################
getconf rotate yes
getconf remove yes
getconf backup yes
getconf keepdaily 5
getconf keepweekly 3
getconf keepmonthly 1
getconf srcconffile
getconf destconffile
getconf srcdir
getconf destdir
getconf current_backup current_backup
getconf desthost
getconf destport 22
getconf destuser
getconf destid_file /root/.ssh/id_rsa
getconf sshoptions
failedcount=0
# strip leading mailbox specifier (eg. mdbox:; maildir:, etc)
stripped_destdir=${destdir/*:/}
stripped_srcdir=${srcdir/*:/}
# strip trailing /
destdir=${destdir%/}
srcdir=${srcdir%/}
if [ -n "$srcconffile" ]; then
srcconffile="-c $srcconffile"
fi
if [ -n "$destconffile" ]; then
destconffile="-c $destconffile"
fi
[ -d $stripped_srcdir ] || fatal "source directory $srcdir doesn't exist"
##################################################################
### FUNCTIONS
function do_user() {
local user=$1
local btype=$2
local letter=${user:0:1}
local target="$stripped_destdir/$letter/$user/$btype.1"
local failedcount=0
local ret=0
debug "syncing"
while [ $failedcount -lt 3 ]; do
debug $DSYNC $testflags -u $user backup $srcconffile \
ssh -i $destid_file $destuser@$desthost $DSYNC $destconffile \
-u $user 2>&1
ret=`$DSYNC $testflags -u $user backup $srcconffile \
ssh -i $destid_file $destuser@$desthost $DSYNC $destconffile \
-u $user 2>&1`
ret=$?
if [ $ret == 2 ]; then
# dsync needs to be run again
let "failedcount = failedcount + 1"
elif [ $ret == 0 ]; then
# things worked, so we break out of the loop
break
ssh -o PasswordAuthentication=no $desthost -l $destuser -i $destid_file $sshoptions "date +%c%n%s > $stripped_destdir/$letter/$user/$btype.1/created"
elif [ $ret != 0 ]; then
# things did not work in a good way, report it and try again
warning "dsync $user failed"
warning " returned: $ret"
let "failedcount = failedcount + 1"
fi
if [ $failedcount -ge 3 ]; then
warning "dsync failed 3 times for this user -- something is not working right. bailing out."
fi
done
}
# remove any maildirs from backup which might have been deleted
# and add new ones which have just been created.
# (actually, it just moved them to the directory "deleted")
function do_remove() {
local tmp1=`maketemp dsync-tmp-file`
local tmp2=`maketemp dsync-tmp-file`
ssh -p $destport -i $destid_file $sshoptions $destuser@$desthost mkdir -p "${stripped_destdir}/deleted"
cd "$stripped_srcdir"
for userdir in `ls -d1 */`; do
ls -1 "$stripped_srcdir/$userdir" | sort > $tmp1
ssh -p $destport -i $destid_file $sshoptions $destuser@$desthost ls -1 "$stripped_destdir/$userdir" | sort > $tmp2
for deluser in `join -v 2 $tmp1 $tmp2`; do
[ "$deluser" != "" ] || continue
info "removing $destuser@$desthost:$stripped_destdir/$userdir$deluser/"
ssh -p $destport -i $destid_file $sshoptions $destuser@$desthost mv "$stripped_destdir/$userdir$deluser/" "$stripped_destdir/deleted"
ssh -p $destport -i $destid_file $sshoptions $destuser@$desthost "date +%c%n%s > '$stripped_destdir/deleted/$deluser/deleted_on'"
done
done
rm $tmp1
rm $tmp2
}
function do_rotate() {
[ "$rotate" == "yes" ] || return;
local user=$1
local letter=${user:0:1}
local backuproot="$stripped_destdir/$letter/$user"
(
ssh -T -o PasswordAuthentication=no $desthost -l $destuser -i $destid_file $sshoptions <<EOF
##### BEGIN REMOTE SCRIPT #####
seconds_daily=86400
seconds_weekly=604800
seconds_monthly=2628000
keepdaily=$keepdaily
keepweekly=$keepweekly
keepmonthly=$keepmonthly
now=\`date +%s\`
if [ ! -d "$backuproot" ]; then
echo "Debug: skipping rotate of $user. $backuproot doesn't exist."
exit
fi
for rottype in daily weekly monthly; do
seconds=\$((seconds_\${rottype}))
dir="$backuproot/\$rottype"
if [ ! -d \$dir.1 ]; then
echo "Debug: \$dir.1 does not exist, skipping."
continue 1
fi
# Rotate the current list of backups, if we can.
oldest=\`find $backuproot -maxdepth 1 -type d -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: \$rottype.\$i --> \$rottype.\$next"
mv \$dir.\$i \$dir.\$next
date +%c%n%s > \$dir.\$next/rotated
else
echo "Debug: skipping rotation of \$dir.\$i because \$dir.\$next already exists."
fi
else
echo "Debug: 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 "Debug: daily.\$max --> 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 "Debug: weekly.\$max --> 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 -maxdepth 1 -type d -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 "Debug: removing rotate.tmp"
rm -rf $backuproot/rotate.tmp
fi
echo "Debug: moving \$rottype.\$i to 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 user=$1
local backuptype=$2
local letter=${user:0:1}
local dir="$stripped_destdir/$letter/$user/$backuptype"
local tmpdir="$stripped_destdir/$letter/$user/rotate.tmp"
(
ssh -T -o PasswordAuthentication=no $desthost -l $destuser -i $destid_file $sshoptions <<EOF
if [ ! -d $stripped_destdir ]; then
echo "Fatal: Destination directory $stripped_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 $tmpdir ]; then
mv $tmpdir $dir.1
if [ \$? == 1 ]; then
echo "Fatal: could not mv $stripped_destdir/rotate.tmp $dir.1 on host $desthost"
exit 1
fi
else
mkdir --parents $dir.1
if [ \$? == 1 ]; then
echo "Fatal: could not create directory $dir.1 on host $desthost"
exit 1
fi
fi
if [ -d $dir.2 ]; then
echo "Debug: update links $backuptype.2 --> $backuptype.1"
cp -alf $dir.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
}
###
##################################################################
# see if we can login
debug "ssh -o PasswordAuthentication=no $desthost -l $destuser -i $destid_file $sshoptions 'echo -n 1'"
if [ ! $test ]; then
result=`ssh -o PasswordAuthentication=no $desthost -l $destuser -i $destid_file $sshoptions 'echo -n 1' 2>&1`
if [ "$result" != "1" ]; then
fatal "Can't connect to $desthost as $destuser using $destid_file."
fi
fi
## SANITY CHECKS ##
status=`ssh -p $destport -i $destid_file $sshoptions $destuser@$desthost "[ -d \"$stripped_destdir\" ] && echo 'ok'"`
if [ "$status" != "ok" ]; then
fatal "Destination directory $stripped_destdir doesn't exist!"
exit
fi
### REMOVE OLD MAILDIRS ###
if [ "$remove" == "yes" ]; then
do_remove
fi
### MAKE BACKUPS ###
if [ "$backup" == "yes" ]; then
if [ $keepdaily -gt 0 ]; then btype=daily
elif [ $keepweekly -gt 0 ]; then btype=weekly
elif [ $keepmonthly -gt 0 ]; then btype=monthly
else fatal "keeping no backups"; fi
if [ "$testuser" != "" ]; then
cd "$stripped_srcdir/${user:0:1}"
do_rotate $testuser
setup_remote_dirs $testuser $btype
do_user $testuser $btype
else
[ -d "$stripped_srcdir" ] || fatal "directory $stripped_srcdir not found."
for user in `@DOVEADM@ user \* | cut -d@ -f1`
do
debug $user
[ "$user" != "" ] || continue
do_rotate $user
setup_remote_dirs $user $btype
do_user $user $btype
done
fi
fi