#!/bin/sh
#	simple backup utility by Nick Manini - v. Oct 2020
#	to be run as cron command at non-hurting (night) times
#	potential problem: keeps overwriting the same file on backupmachine
#	over and over again: if crash during backup then all is lost
#	cure: weekly or monthly copy the backupfile to another name or dir
#	(could be automated...)

backupdirectory=/home/manini	# the local directory to backup
excludeddirectoryfile="EXCLUDE_FROM_BACKUP"	# put this file in a directory not intended for backup
prefix=all.`basename $backupdirectory`.`hostname`
tmpdir=/scratch
#tmpdir=~/scratch	# temporary solution
tarf=$prefix.tgz
ttarf=$tmpdir/$tarf
backupmachine=pga		    	# the remote machine
copycommand="scp "			# rcp or scp
#   (setup either .rhost or .ssh/authorized_keys so that no passwd is asked!)
remoteshell="ssh ";			# rsh or ssh work - configure correcly!
remoterun="$remoteshell $backupmachine -n";

umask 077				# set very safe priorities

#rm $ttarf $tmpdir/$prefix[a-z][a-z]
#echo backup suspended!!
#exit 1

echo "backup of $backupdirectory -> $backupmachine starting on "`date`

tar czf $ttarf --exclude-tag-all=$excludeddirectoryfile $backupdirectory
tarRV=$?
if (test $tarRV -lt 2)
then	# check for correct tar-gzipping before messing up the backup
    if(test $tarRV -eq 1)
    then
	echo "Warning, some file may have changed and not entered in tar"
    fi       
    if($copycommand $ttarf $backupmachine:)
    then
	rm $ttarf	# cleanup on successful completion
    else
	date
	echo $copycommand error! could not copy the tar file!
	echo leaving local copy $tmpdir/$ttarf for investigation
	echo terminating here
	exit 3
    fi
else
    date
    echo tar error! leaving the $ttarf file uncopied for investigation
    echo terminating here
    exit 1
fi
echo backup completed successfully on `date`