X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=backup.sh;h=ae4067859d755df691d2ac4747caadc871420a0e;hb=255cc8f7d17aeb999055bf42675d8786681c9378;hp=49a643d87c29de676af1b9adeefeeff7daa83d77;hpb=66ccd8c7f77e01e7918db16c77459544ceac5f95;p=backup.sh

diff --git a/backup.sh b/backup.sh
index 49a643d..ae40678 100755
--- a/backup.sh
+++ b/backup.sh
@@ -1,14 +1,74 @@
-#!/bin/bash
-
-#dirs
-confdir=/home/backup/conf/           #configuration files
-storagedir=/backup                   #mountpoint of huge disc
-###
+#!/bin/sh
+# 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:
+#
+# KISS. And by that I mean really simple. Only regular Unix commands, please
+# (but GNU extensions are used).
+#
+# 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 computers are backed up in parallell (but the filesystems on each
+# computer in serial). This is implemented highly simplistic, with forking
+# subshells. The script has no concept about threads, and stuff might go wrong,
+# which usually requires manual cleanups.
+#
+# The script is halfway Norwegian and halfway English. Newer modifications are
+# in English, we should probably stick to that.
+# 
+# Known issues:
+#
+# o $R has no proper meaning because of the forking subshell stuff. We need a
+#   more robust way of returning non-zero on errors, which we probably don't
+#   right now.
+# o The code around line 211 and downwards is messy.
+#
+
+# Configuration
+LOCKFILE=/home/backup/backuprun.lockfile
+confdir=/home/backup/conf/           # Configuration files
+storagedir=/backup                   # Where we keep backups
+maksantallfulle=3                    # Number of full backups
+dagermellomfulle=30                  # Days between full backups
+DATE=`date "+%Y%m%d%H%M"`            #format: touch
+DATEs=`date "+%Y-%m-%d %H:%M"`       #format: tar
 
-#exclude-pattern
+# Exclude-pattern
 exclude=$confdir/exclude
 [ ! -f $exclude ] && printf "tmp\ncore\n" > $exclude
-###
+
+# Initially, we consider everything to be just fine.
+R=0
+
+# Die more or less gracefully (at least notify user)
+die() {
+	echo `date`": Something nasty happened, and since I fork a lot:"
+        echo `date`": I CANNOT CLEAN UP THE MESS MYSELF."
+	echo `date`": You need to get rid of lost process named stuff like $0, tar and ssh."
+	exit 255
+}
+
+# Trap C-c and kill
+trap die SIGINT SIGTERM
+
+# Don't start if we're already running
+if [ -e $LOCKFILE ]; then
+	echo `date`": $LOCKFILE exists for pid `cat $LOCKFILE`, exiting."
+	echo `date`": $LOCKFILE exists for pid `cat $LOCKFILE`, exiting." >&2
+	exit 1
+fi;
+touch $LOCKFILE
+echo $$ > $LOCKFILE
 
 #syntax of remotestat:
 #hostname:/directory/
@@ -19,30 +79,20 @@ remotestatf=$confdir/remotestat
 PATH=/local/bin:$PATH:/store/bin
 export PATH
 
-#start the logfile
-date
-echo
-echo "Exclude pattern:"
-cat $exclude
-echo
-echo
+echo `date`": Backup run starting" >&2
 
 umask 027
 
 # The computers we want to back up
-unixcomputers=`cat $confdir/computers.unix`
-###
+unixcomputers=`cat $confdir/computers.unix \
+  | grep -v "^#" \
+  | grep -v "^$" `
 
-#disse bør kunne varieres fra fs til fs?
-maksantallfulle=2          #hvor mange fulle vi tar vare på
-dagermellomfulle=30        #antall dager før det er på tide med ny full
-logw=40
-###
+# Backup only one computer, from command line?
+if [ $1 ] ; then 
+  unixcomputers=$1
+fi;
 
-#lager datovariabeler
-DATE=`date "+%Y%m%d%H%M"`            #format: touch
-DATEs=`date "+%Y-%m-%d %H:%M"`       #format: tar
-###
 
 #selve backupen
 # krever at noen variabler er satt
@@ -50,144 +100,219 @@ DATEs=`date "+%Y-%m-%d %H:%M"`       #format: tar
 backup()
 {
 
- printf "%-${logw}s %s\n" "$computer:$filesystem" "$backuplevel backup"
+ echo -n `date` >&2
+ printf " $computer: $computer:$filesystem $backuplevel backup" >&2
 
  if [ "$backuplevel" = "daglig" ] || [ "$backuplevel" = "incremental" ]
  then
   lastd=`cat ../.date`
-  lastcmd="--newer=\"$lastd\""
+  lastcmd="--newer='$lastd'"
  else
   lastcmd=""
  fi
 
  #if this client has a special tar
- $tar=${TAR:-tar}
- unset TAR
-
- #We try to run tar on the remote computer
- #need to specify a special tar on some clients. how?
- if `ssh $computer "cd $filesystem ;\
-     $tar cfl - . $lastcmd \
-      --exclude-from=/tmp/.backup/exclude \
-        | gzip" \
-   |  dd of=$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
+ #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 root@$computer "ls ~/.backup/exclude"`
+
+ # We try to run tar on the remote computer
+ #    z gzip it
+ #    c create archive
+ #    C change to directory first
+ #    . where to start taring (see C)
+ #    $lastcmd only files newer than this
+ #    --one-file-system don't traverse file systems
+ #    --exclude-from file to get exclusion pattern from
+ #    Pipe the stuff over ssh to ourselves, run pee to cat the contents to a
+ #    file and build a file list, respectivly.  
+ TARFILE=$DATE.tmp
+ TARCMD="ssh root@$computer \"$tar --one-file-system -zcf - -C $filesystem . $lastcmd \
+	--exclude-from=$exf\" | pee \"cat > $TARFILE\" \"tar tzvf -\""
+ echo `date`" $computer: Running $TARCMD" >&2
+ eval $TARCMD > $DATE.idx
+
+ if [ -s $TARFILE ]; then
+  # File is >0 in size, we assume it worked.
+
+  # Move tar file in place
+  mv $TARFILE $DATE.tgz
+
+  # Update timestamp
+  echo $DATEs > ../.date && touch -t $DATE ../.date
+
+  # Make a sorted filelist as well
+  sort -k6 < $DATE.idx > $DATE.sdx
+
+  # Fix permissions
   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"
+  # Something wrong happened.
+  rm $TARFILE
+  echo `date`" $computer: $TARFILE empty. $backuplevel backup of $computer:$filesystem failed and deleted"
+
+  # We don't want to return 0
+  R=1
  fi
 
 }
 
-#Løper gjennom listen av unixmaskiner som vi skal ta backup av
 for computer in $unixcomputers
 do
+( 
+ # Check that the target filesystem is mounted (actually check that it's not
+ # the root filesystem)
+ rootfilesystem=`df -P /`
+ targetfilesystem=`df -P "$storagedir/$computer"`
+ if [ "$rootfilesystem" == "$targetfilesystem" ]; then
+ 	echo `date`" $computer: Target filesystem ($storagedir/$computer) was mounted on /. Aborting"
+	continue
+ fi
+
+ echo `date`" $computer: Backing up $computer" >&2
+
+ # Try to SSH to the computer without entering a password.
+ if ! `ssh -n -o NumberOfPasswordPrompts=0 root@$computer /bin/true`; then
+  echo `date`" $computer: Could not use passwordless SSH."
+
+  # We don't want to return 0
+  R=1
+  # Do next computer
+  continue;
+ fi
  
- #tømmer variabelen for sikkerhets skyld
  filesystems=""
 
- #Sjekker nest siste felt i fstab. Om det er 0 tar vi ikke backup
- filesystems=`ssh -n $computer "cat /etc/fstab" \
+ # Check dump bit in fstab
+ filesystems=`ssh -n root@$computer "cat /etc/fstab" \
   | grep -v nfs \
-  | grep -v ^# \
+  | grep -v "^#" \
+  | grep -v "^$" \
   | awk '{ if ( $(NF-1) != "0" ) print $2}' `
 
- #clean up our dir at this client
- ssh $computer "rm -rf /tmp/.backup ; mkdir -m 700 /tmp/.backup"
+ # Clean up our dir at this client
+ if ! ssh root@$computer "rm -r ~/.backup ; mkdir -m 700 ~/.backup"; then
+  echo `date`" $computer: Could not create backup staging area at $computer:~/.backup - skipping backup of $computer"
+  R=1
+  continue;
+ fi
 
- #try to copy $exclude to $computer
- scp $exclude $computer:/tmp/.backup/exclude ||
-    echo "could not copy exclude.txt to $computer :("
+ # Try to copy $exclude to $computer
+ if ! scp $exclude root@$computer:~/.backup/exclude > /dev/null; then
+  echo `date`" $computer: Could not copy exclude.txt to $computer - skipping backup of $computer"
+  R=1
+  continue;
+ fi
 
- #try to copy preeexec and postexec if they exist
- [ -f $confdir/preexec.$computer ] &&
-    scp $confdir/preexec.$computer  $computer:/tmp/.backup/preexec
- [ -f $confdir/postexec.$computer ] &&
-    scp $confdir/postexec.$computer $computer:/tmp/.backup/postexec
+ # Try to copy preeexec and postexec if they exist
+# TODO: Gah, clean this mess!
+ [ -f $confdir/preexec.$computer ] && (
+    scp $confdir/preexec.$computer  root@$computer:~/.backup/preexec >&2 ||
+     ( echo `date`" $computer: Could not copy preexec.$computer to $computer:~/.backup/preexec - skipping backup of $computer"
+       R=1
+       continue
+     )
+    )
+ [ -f $confdir/postexec.$computer ] && (
+    scp $confdir/postexec.$computer root@$computer:~/.backup/postexec >&2 ||
+     ( echo `date`" $computer: Could not copy postexec.$computer to $computer:~/.backup/postexec - skipping backup of $computer"
+       R=1
+       continue
+     )
+    )
+
+ # Try to run preexec if it exist
+ if ! ssh root@$computer "[ ! -f ~/.backup/preexec ] || /bin/bash -x ~/.backup/preexec" >&2; then
+ 	echo `date`" $computer: Could not run $computer:~/.backup/preexec - skipping backup of $computer"
+	R=1
+	continue
+ fi
 
- #try to run preexec if it exist
- ssh $computer "[ -f /tmp/.backup/preexec ] && /bin/bash -x /tmp/.backup/preexec"
 
  for filesystem in $filesystems
  do
-  #lager en variant uten tegnet "/" eller $ (gjelder NT)
+  # Remove / and $ (for Windows) for path names
   sfilesystem=`echo $filesystem | tr '\/\$' '__'`
 
-  #lager det som trengs av kataloger
+  # Prepare storage area
   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
+  # Default backuplevel
   backuplevel=daglig
 
   if [ ! -f $storagedir/$computer/$sfilesystem/.date ]
   then
-   #take the first full backup of this filesystem on this computer
+   # 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
+  # Check if we want a full backup
+  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
+  # We want to be here
+  cd $storagedir/$computer/$sfilesystem/$backuplevel || die
 
-  #perform the actual backup
+  # Perform the actual backup
   backup
 
-  #delete complete backups
-  mf=$(($maksantallfulle+1))
-  for full in `ls -1t $storagedir/$computer/$sfilesystem/full/*tgz | tail +$mf`
+  # Check if this box has a custom number of full backups
+  if [ -f $confdir/maksfulle.$computer ] ; then
+    mf=$((`cat $confdir/maksfulle.$computer`+1))
+  else
+    mf=$(($maksantallfulle+1))
+  fi
+
+  # Delete old full backups
+  for full in `ls -1t $storagedir/$computer/$sfilesystem/full/*tgz | tail -n +$mf`
   do
-   prefix=`echo $full|cut -d . -f 1`
-   echo "$computer:$filesystem sletter full $prefix (for mange)"
+   prefix=`echo $full | sed "s/\.[^.]*$//"`
+   echo `date`": $computer:$filesystem Deleting full backup $prefix" >&2
    rm $prefix*
   done
 
-  #delete incremental backups older than the oldest complete backup
+  # 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 $oldf \
-     -exec rm {} \;
-     #denne funker bare med gnu find
-     #-printf "$computer:$filesystem sletter daglig %f (for gammel)\n" \
-
+     -printf "`date`: $computer: Deleting old incremental backup: %p\n" \
+     -exec rm {} \; >&2
  done
 
- #try to run postexec if it exist
- ssh $computer "[ -f /tmp/.backup/postexec ] && /bin/bash -x /tmp/.backup/postexec"
+ # Try to run postexec if it exist
+ if ! ssh root@$computer "[ ! -f ~/.backup/postexec ] || /bin/bash -x ~/.backup/postexec" >&2; then
+ 	echo `date`" $computer: Could not run $computer:~/.backup/postexec"
+	R=1
+ fi
 
+) &
 done
 
-#create report
-/home/backup/report.sh $storagedir > /tmp/report.txt
-[ ! -z $remotestat ] && scp /tmp/report.txt $remotestat
-###
+wait
+
+# Remove lockfile
+rm $LOCKFILE
 
-date
+# Did anything go wrong?
+# (IMPORTANT NOTE: The R-business does not work as expected, since this script
+# forks itself).
+if [ $R != 0 ]; then
+	echo `date`": Backup run ended with errors, check logs."
+	exit 1
+else
+	echo `date`": Backup run ended" >&2
+fi