check if rsync installed

rsync_backup.sh

@@ -19,6 +19,12 @@ delete_archive=true
 archive_with_date=true
 #archive_with_date=false
 
+if ! which rsync >/dev/null 2>&1; then
+  echo "rsync is not installed. Installing..."
+  sudo apt-get update
+  sudo apt-get install -y rsync
+fi
+
 if [ "$mode" == "files" ]; then
   rsync -a --exclude-from=$exclude_file --password-file=$password_file $source $user@$ip::$destination
 else