X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=backup.sh;h=b808d5611e49636cec8adf41705ab2f7b6aaac01;hb=f5e26aba1db0b44ffd29cb239532fa42c002cbce;hp=a7256a9a7cfd2270ab1b80f1252bb8770c501a22;hpb=7e41ce51a46e60c9f56ff339fecbe22b66714548;p=backup.sh

diff --git a/backup.sh b/backup.sh
index a7256a9..b808d56 100755
--- a/backup.sh
+++ b/backup.sh
@@ -1,204 +1,358 @@
 #!/bin/bash
+# backup.sh
+# 
+# Backup up Unix-like computers
+# 
+# itk@samfundet.no
+#
+# This script was first checked into RCS in 2000, and has since backed up a few
+# servers almost every day, whenever not broken.
+# 
+# It's a bit peculiar, but quite effective. The following is worth keeping in
+# mind when hacking:
+#
+# Because of the way we run this script from cron, informational logging goes
+# to stderr and warnings and errors to stdout. This way, we get mail whenever
+# stuff fails, and other output is redirected to the log file.
+# 
+# The script is halfway Norwegian and halfway English. Newer modifications are
+# in English, we should probably stick to that.
+
+computer=$1                                      # The computer to backup.
+SCRIPTPATH="$( cd "$(dirname "$0")" ; pwd -P )"  # Absolute directory the script lives in
+confdir=$SCRIPTPATH/conf                         # Directory for configuration files
+conffile=$confdir/backup.config
+LOCKFILE=$SCRIPTPATH/backuprun.lockfile.$computer
+DAY_OF_MONTH=`date "+%d" | sed s/^0//`           # from 1 to 31
+DATE=`date "+%Y%m%d%H%M"`                        # format: touch
+DATEs=`date "+%Y-%m-%d %H:%M"`                   # format: tar
+TOP_PID=$$
+
+if [ -z "$computer" ]; then
+	echo "Usage: $0 COMPUTER"
+	exit 1
+fi
 
-#dirs
-confdir=/home/backup/conf/           #configuration files
-storagedir=/backup                   #mountpoint of huge disc
-###
-
-#exclude-pattern
-exclude=$confdir/exclude
 [ ! -f $exclude ] && printf "tmp\ncore\n" > $exclude
-###
-
-#syntax of remotestat:
-#hostname:/directory/
-remotestatf=$confdir/remotestat
-[ -f $remotestatf ] && remotestat=`cat $remotestatf`
-###
 
-PATH=/local/bin:$PATH:/store/bin
-export PATH
-
-#start the logfile
-date
-echo
-echo "Exclude pattern:"
-cat $exclude
-echo
-echo
+# Die more or less gracefully (at least notify user)
+die() {
+	warnmsg "Aborting."
+	rm $LOCKFILE
+	exit 1
+}
+diemsg() {
+	warnmsg "$@"
+	die
+}
+warnmsg() {
+	echo `date`": $computer: $@"
+	echo `date`": $computer: $@" >&2
+}
+infomsg() {
+	echo `date`": $computer: $@" >&2
+}
+findconf() {  # getconf is already taken
+	key=$1
+	computer=$2
+	filesystem=$( echo $3 | tr / . )
+
+	if [ "$computer" ] && [ "$filesystem" ] && git config -f $conffile $computer$filesystem.$key > /dev/null; then
+		git config -f $conffile $computer$filesystem.$key
+	elif [ "$computer" ] && git config -f $conffile $computer.$key > /dev/null; then
+		git config -f $conffile $computer.$key
+	elif git config -f $conffile defaults.$key > /dev/null; then
+		git config -f $conffile defaults.$key
+	else
+		warnmsg "No configuration found for $key in $conffile, aborting."
+		kill -TERM $TOP_PID
+	fi
+}
 
-umask 027
+# Trap C-c and kill
+trap die SIGINT SIGTERM
 
-# The computers we want to back up
-unixcomputers=`cat $confdir/computers.unix`
-###
+# Don't start if we're already running. Don't use diemsg, as that removes the lock file!
+if [ -e $LOCKFILE ]; then
+	warnmsg "$LOCKFILE exists for pid `cat $LOCKFILE`."
+	exit 1
+fi;
+touch $LOCKFILE
+echo $$ > $LOCKFILE
 
-#disse bør kunne varieres fra fs til fs?
-maksantallfulle=3          #hvor mange fulle vi tar vare på
-dagermellomfulle=30        #antall dager før det er på tide med ny full
-logw=40
-###
+infomsg "Backup run starting"
 
-#lager datovariabeler
-DATE=`date "+%Y%m%d%H%M"`            #format: touch
-DATEs=`date "+%Y-%m-%d %H:%M"`       #format: tar
-###
+umask 027
 
-#selve backupen
-# krever at noen variabler er satt
-# krever at vi er i rett katalog
 backup()
 {
+	infomsg "$computer:$filesystem $backuplevel backup"
+
+	localsnar="${storagedir}/${computer}/${sfilesystem}/.incremental.snar"
+	remotesnar="$remotehome/.backup/${sfilesystem}.snar"
+	if [ "$backuplevel" = "daglig" ]; then
+		# If incremental backup, we need to copy the incremental status to $computer.
+		# If it does not exist, whine a bit and then run date-based instead.
+		if [ -s "$localsnar" ]; then
+			if ! scp $localsnar $username@$computer:$remotesnar >&2; then
+				diemsg "Could not copy .incremental.snar to $computer"
+			fi
+			lastcmd="--listed-incremental=$remotesnar --no-check-device"
+		else
+			infomsg "Missing incremental.snar for $filesystem, doing date-based backup instead until next full backup"
+			remotesnar=""
+			lastd=`cat ../.date`
+			lastcmd="--newer='$lastd'"
+		fi
+	else
+		# Note: Since we rm-ed .backup previously, and we don't scp over
+		# anything in this branch, this file will not exist, and we
+		# will be doing a full backup (but we want the output of it).
+		lastcmd="--listed-incremental=$remotesnar"
+	fi
+
+	# The file is usually stored to disk with a simple cat > $TARFILE,
+	# but in some cases, like backing up to a remote and untrusted
+	# file system, it could be useful to replace it with e.g.
+	# a GPG command line.
+	storageprogram=$( findconf storageprogram $computer $sfilesystem )
+
+	# We try to run tar on the remote computer
+	#    c create archive
+	#    C change to directory first
+	#    . where to start taring (see C)
+	#    $lastcmd only files newer than this
+	#    --one-file-system don't traverse file systems
+	#    --use-compress-program compress it using gzip or pigz
+	#    --exclude-from file to get exclusion pattern from
+	#    Pipe the stuff over ssh to ourselves, run pee to cat the contents to a
+	#    file and build a file list, respectivly.  
+	TARFILE=$DATE.tmp
+	TARCMD="ssh -n $username@$computer \"$nice tar --one-file-system --use-compress-program $compressor -cf - -C $filesystem . $lastcmd \
+		--exclude-from=$remotehome/.backup/exclude\" | pee \"$storageprogram > $TARFILE\" \"tar tzvf -\""
+	infomsg "Running $TARCMD"
+	eval $TARCMD > $DATE.idx
+
+	if [ $? -eq 0 ] && [ -s $TARFILE ]; then
+		# File is >0 in size and neither cat or tar tzvf failed; we assume it worked.
+ 
+		if [ "$remotesnar" ]; then
+			if ! scp $username@$computer:$remotesnar $localsnar.tmp >&2; then
+				diemsg "Could not copy .incremental.snar from $computer"
+			fi
+		fi
+
+		# Move tar file in place
+		mv $TARFILE $DATE.tgz
+		if [ "$remotesnar" ]; then
+			mv $localsnar.tmp $localsnar
+		fi
+
+		# Update timestamp
+		echo $DATEs > ../.date && touch -t $DATE ../.date
+
+		# Fix permissions
+		chmod 600 *tgz                      #only for us
+		chmod 644 *idx 2>/dev/null          #everyone can read
+
+		# Let the remote computer know that we ran a successful backup (for nagios)
+		ssh -n $username@$computer touch $filesystem/.lastbackup
+	else
+		# Something wrong happened.
+		rm $TARFILE
+		diemsg "tar failed or $TARFILE empty. $backuplevel backup of $computer:$filesystem failed and deleted"
+	fi
+}
 
- printf "%-${logw}s %s\n" "$computer:$filesystem" "$backuplevel backup"
-
- if [ "$backuplevel" = "daglig" ] || [ "$backuplevel" = "incremental" ]
- then
-  lastd=`cat ../.date`
-  lastcmd="--newer=\"$lastd\""
- else
-  lastcmd=""
- fi
-
- #if this client has a special tar
- #we need to find a better solution to this conf-issue
- if [ -f $confdir/tar.$computer ] ; then
-   tar=`cat $confdir/tar.$computer`
- else 
-   tar=tar
- fi
-
- #expand the exclude-path for use with tar
- exf=`ssh $computer "ls ~/.backup/exclude"`
-
- #We try to run tar on the remote computer
- #    C is instead of 'cd $filesystem'
- #    - is 'this directory'
- #    l is 'stay in local filesystem
- if `ssh $computer "$tar cfCl - $filesystem . $lastcmd \
-      --exclude-from=$exf \
-        | gzip" \
-   |  dd of=$DATE.tmp 2>/dev/null` 
- then
-  #perhaps it did work
-  mv $DATE.tmp $DATE.tgz
-  #make a filelist.
-  #update the datefile if the filelist is ok.
-  tar tvfz $DATE.tgz > $DATE.idx 2>&1 &&
-    echo $DATEs > ../.date            &&
-    touch -t $DATE ../.date
-
-  #make a sortet filelist
-  grep -v ^d $DATE.idx | sort -n -r +2 > $DATE.sdx
-
-  #fix perm
-  chmod 600 *tgz                      #only for us
-  chmod 644 *sdx *idx 2>/dev/null     #everyone can read
-
- else
-  #it did not work
-  rm $DATE.tmp 2>/dev/null
-  echo "$backuplevel backup of $computer:$filesystem failed and deleted"
- fi
-
+# Non-privileged backups currently have a few limitations compared to regular ones:
+#
+#  - No .idx files.
+#  - No .snar-style incremental backups, only date-based.
+#  - No touching of .lastbackup for Nagios.
+#  - Failed tar operations may go undetected, since we only see the error code
+#    the last process in the pipe chain, which is gpg.
+#  - No storageprogram support (see above), because the file is typically already
+#    encrypted.
+nonprivbackup()
+{
+	infomsg "$computer:$filesystem $backuplevel non-privileged backup"
+
+	if [ "$backuplevel" = "daglig" ]; then
+		lastd=`cat ../.date`
+		lastcmd="'$lastd'"
+	else
+		lastcmd=""
+	fi
+
+	TARFILE=$DATE.tmp
+	TARCMD="ssh -n $username@$computer \"sudo /usr/local/sbin/output-encrypted-backup $filesystem $lastcmd\""
+	infomsg "Running $TARCMD"
+	eval $TARCMD > $TARFILE
+
+	if [ $? -eq 0 ] && [ -s $TARFILE ]; then
+		# File is >0 in size and the remote side did not report any fatal errors; we assume it worked.
+
+		# Move tar file in place
+		mv $TARFILE $DATE.tgz.gpg
+
+		# Update timestamp
+		echo $DATEs > ../.date && touch -t $DATE ../.date
+
+		# Fix permissions
+		chmod 600 *tgz.gpg                  #only for us
+	else
+		# Something wrong happened.
+		rm $TARFILE
+		diemsg "tar failed or $TARFILE empty. $backuplevel backup of $computer:$filesystem failed and deleted"
+	fi
 }
 
-#Løper gjennom listen av unixmaskiner som vi skal ta backup av
-for computer in $unixcomputers
-do
+# Get basic configuration.
+storagedir=$( findconf storagedir $computer )
+username=$( findconf username $computer )
+exclude=$( findconf excludefile $computer )
+
+# Check that the target filesystem is mounted (actually check that it's not
+# the root filesystem)
+if [ ! -d "$storagedir/$computer" ]; then
+	diemsg "Target filesystem ($storagedir/$computer) does not exist."
+fi
+rootfilesystem=`df -P /`
+targetfilesystem=`df -P "$storagedir/$computer"`
+if [ "$rootfilesystem" == "$targetfilesystem" ]; then
+	diemsg "Target filesystem ($storagedir/$computer) was mounted on /."
+fi
  
- #tømmer variabelen for sikkerhets skyld
- filesystems=""
-
- #Sjekker nest siste felt i fstab. Om det er 0 tar vi ikke backup
- filesystems=`ssh -n $computer "cat /etc/fstab" \
-  | grep -v nfs \
-  | grep -v ^# \
-  | awk '{ if ( $(NF-1) != "0" ) print $2}' `
-
- #clean up our dir at this client
- ssh $computer "rm -r ~/.backup ; mkdir -m 700 ~/.backup"
-
- #try to copy $exclude to $computer
- scp $exclude $computer:~/.backup/exclude ||
-    echo "could not copy exclude.txt to $computer :("
-
- #try to copy preeexec and postexec if they exist
- [ -f $confdir/preexec.$computer ] &&
-    scp $confdir/preexec.$computer  $computer:~/.backup/preexec
- [ -f $confdir/postexec.$computer ] &&
-    scp $confdir/postexec.$computer $computer:~/.backup/postexec
-
- #try to run preexec if it exist
- ssh $computer "[ -f ~/.backup/preexec ] && /bin/bash -x ~/.backup/preexec"
-
- for filesystem in $filesystems
- do
-  #lager en variant uten tegnet "/" eller $ (gjelder NT)
-  sfilesystem=`echo $filesystem | tr '\/\$' '__'`
-
-  #lager det som trengs av kataloger
-  mkdir -m 755 -p $storagedir/$computer/$sfilesystem/{full,daglig} 2>/dev/null
-
-  #
-  echo $filesystem > ${storagedir}/${computer}/.${sfilesystem}.name 
-  chmod 644 ${storagedir}/${computer}/.${sfilesystem}.name
-
-  #set default backuplevel
-  backuplevel=daglig
-
-  if [ ! -f $storagedir/$computer/$sfilesystem/.date ]
-  then
-   #take the first full backup of this filesystem on this computer
-   backuplevel=full
-   echo $DATEs > $storagedir/$computer/$sfilesystem/.date
-  fi
-
-  #sjekker om det er på tide med en full
-  if 
- [ -z "`find $storagedir/$computer/$sfilesystem/full/ -name \*tgz -mtime -$dagermellomfulle`" ]
-  then
-   backuplevel=full
-  fi
- 
-  #gå ned i rett katalog
-  cd $storagedir/$computer/$sfilesystem/$backuplevel
-
-  #perform the actual backup
-  backup
-
-  #delete complete backups
-  mf=$(($maksantallfulle+1))
-  for full in `ls -1t $storagedir/$computer/$sfilesystem/full/*tgz | tail +$mf`
-  do
-   prefix=`echo $full|cut -d . -f 1`
-   echo "$computer:$filesystem sletter full $prefix (for mange)"
-   rm $prefix*
-  done
-
-  #delete incremental backups older than the oldest complete backup
-  oldf=`ls -t1 $storagedir/$computer/$sfilesystem/full/*tgz | tail -1`
-  find \
-     $storagedir/$computer/$sfilesystem/daglig \
-     -type f \
-     \! -newer $oldf \
-     -exec rm {} \;
-     #denne funker bare med gnu find
-     #-printf "$computer:$filesystem sletter daglig %f (for gammel)\n" \
-
- done
-
- #try to run postexec if it exist
- ssh $computer "[ -f ~/.backup/postexec ] && /bin/bash -x ~/.backup/postexec"
-
+infomsg "Backing up $computer"
+
+# Try to SSH to the computer without entering a password.
+if ! ssh -n -o NumberOfPasswordPrompts=0 $username@$computer /bin/true; then
+	diemsg "Could not use passwordless SSH."
+fi
+
+# Find the home directory of the backup user
+remotehome=`ssh -n $username@$computer "echo ~"`
+if [ -z "$remotehome" ]; then
+	diemsg "Could not expand ~ for user $username"
+fi
+
+# Check if pigz is available
+if ssh -n $username@$computer "pigz -V 2>/dev/null"; then
+	compressor=pigz
+else
+	infomsg "pigz missing; falling back to gzip."
+	compressor=gzip
+fi
+
+# Check if nice and ionice are available
+if ssh -n $username@$computer "nice -n 19 ionice -c3 /bin/true 2>/dev/null"; then
+	nice="nice -n 19 ionice -c3"
+else
+	infomsg "nice and/or ionice missing; will run at normal priority."
+	nice=""
+fi
+
+# Check dump bit in fstab
+filesystems=`ssh -n $username@$computer "cat /etc/fstab" \
+	| grep -v nfs \
+	| grep -v "^#" \
+	| grep -v "^$" \
+	| awk '{ if ( $(NF-1) != "0" ) print $2}' `
+
+# Clean up our dir at this client
+if ! ssh -n $username@$computer "rm -r $remotehome/.backup ; mkdir -m 700 $remotehome/.backup"; then
+	diemsg "Could not create backup staging area at $computer:$remotehome/.backup"
+fi
+
+# Try to copy $exclude to $computer
+if ! scp $exclude $username@$computer:$remotehome/.backup/exclude >&2; then
+	diemsg "Could not copy exclude.txt to $computer"
+fi
+
+# Try to copy preeexec and postexec if they exist
+if [ -f $confdir/preexec.$computer ]; then
+	if ! scp $confdir/preexec.$computer $username@$computer:$remotehome/.backup/preexec >&2; then
+		diemsg "Could not copy preexec.$computer to $computer:$remotehome/.backup/preexec"
+	fi
+fi
+if [ -f $confdir/postexec.$computer ]; then
+	if ! scp $confdir/postexec.$computer $username@$computer:$remotehome/.backup/postexec >&2; then
+		diemsg "Could not copy postexec.$computer to $computer:$remotehome/.backup/postexec"
+	fi
+fi
+
+# Try to run preexec if it exists
+if ! ssh -n $username@$computer "[ ! -f $remotehome/.backup/preexec ] || /bin/bash -x $remotehome/.backup/preexec" >&2; then
+	diemsg "Could not run $computer:$remotehome/.backup/preexec"
+fi
+
+for filesystem in $filesystems; do
+	# Remove / and $ (for Windows) for path names
+	sfilesystem=`echo $filesystem | tr '\/\$' '__'`
+
+	# Prepare storage area
+	mkdir -m 755 -p $storagedir/$computer/$sfilesystem/full 2>/dev/null
+	mkdir -m 755 -p $storagedir/$computer/$sfilesystem/daglig 2>/dev/null
+
+	# Default backuplevel
+	backuplevel=daglig
+
+	if [ ! -s $storagedir/$computer/$sfilesystem/.date ]; then
+		# Take the first full backup of this filesystem on this computer
+		backuplevel=full
+	fi
+
+	# Check if we want a full backup
+	fixedfullbackupday=$( findconf fixedfullbackupday $computer $filesystem )
+	if [ "$fixedfullbackupday" ]; then
+		fullbackup_min_for_this_machine=$( findconf daysbetweenfullforfixed $computer $filesystem )
+		if [ "$DAY_OF_MONTH" = "$fixedfullbackupday" ]; then
+			backuplevel=full
+		fi
+	else
+		fullbackup_min_for_this_machine=$( findconf daysbetweenfull $computer $filesystem )
+	fi
+
+	if [ -z "`find $storagedir/$computer/$sfilesystem/full/ -name \*tgz\* -mtime -$fullbackup_min_for_this_machine`" ]; then
+		backuplevel=full
+	fi
+
+	# We want to be here
+	cd $storagedir/$computer/$sfilesystem/$backuplevel || diemsg "$storagedir/$computer/$sfilesystem/$backuplevel does not exist"
+
+	# Perform the actual backup
+	if [ "$( findconf nonpriv $computer )" ]; then
+		nonprivbackup
+	else
+		backup
+	fi
+
+	# Delete old full backups
+	mf=$( findconf maxnumfull $computer $filesystem )
+	mf=$(( mf + 1 ))
+	for full in `ls -1t $storagedir/$computer/$sfilesystem/full/*tgz* | tail -n +$mf`; do
+		prefix=`echo $full | sed "s/\.[^.]*$//"`
+		infomsg "$computer:$filesystem Deleting full backup $prefix"
+		rm $prefix*
+	done
+
+	# Delete incremental backups older than the oldest full backup
+	oldf=`ls -t1 $storagedir/$computer/$sfilesystem/full/*tgz* | tail -1`
+	find \
+		$storagedir/$computer/$sfilesystem/daglig \
+		-type f \
+		\! -newer $oldf \
+		-printf "`date`: $computer: Deleting old incremental backup: %p\n" \
+		-exec rm {} \; >&2
 done
 
-#create report
-/home/backup/report.sh $storagedir > /tmp/report.txt
-#[ ! -z $remotestat ] && scp /tmp/report.txt $remotestat
-###
+# Try to run postexec if it exist
+if ! ssh -n $username@$computer "[ ! -f $remotehome/.backup/postexec ] || /bin/bash -x $remotehome/.backup/postexec" >&2; then
+	diemsg "Could not run $computer:$remotehome/.backup/postexec"
+fi
 
-# print diskusage to logfile
-df -k
+# Use warn so that we will get an email even on success.
+warnmsg "Backup completed successfully."
 
-date
+# Remove lockfile
+rm $LOCKFILE