#!/bin/bash
target=$1
today=$(date +%F)
for file in `ls $target`
do
  FileSize=$(du -k $target"/"$file | cut -f1)
  if [ ${file: -4} == ".log" -a $FileSize -gt 5000 ]
  then
    newfile="${file}.old"
    mv $target"/"$file $target"/"$newfile
    touch $target"/"$file
  fi
done
cd $target
tar -czvf "logs.old."$today".tar" *.old
rm *.old