XwZ

dir_logs="/home/logs"
dir_logs_dest="/home/logs_save"
for annee in `ls ${dir_logs}`
do
#echo "Analyse de l'anne : ${annee}"

	for mois in `ls ${dir_logs}/${annee}/`
	do
#		echo "Analyse du mois : ${mois}/${annee}"
		mkdir ${dir_logs_dest}/${annee}

		for jours in `ls ${dir_logs}/${annee}/${mois}/`
		do
#			echo "Dplacer le log du ${jours}-${mois}-${annee}/monsite.log"
			mkdir ${dir_logs_dest}/${annee}/${mois}

			for file in `ls ${dir_logs}/${annee}/${mois}/${jours}/ | grep .log`
			do
				cp "${dir_logs}/${annee}/${mois}/${jours}/${file}" "${dir_logs_dest}/${annee}/${mois}/${jours}_${file}"
			done
		done
	done
done