如何利用TAR備份資料

#!/bin/sh

backup_dir="/root/backup"

#you backup dir
dir1="/etc"
dir2="/var/log"

#name of back

dir1_name="etc.tar.gz"
dir2_name="log.tar.gz"

# execute backup command

cd $backup_dir

tar cvfz `date +%Y-%m`-${dir1_name} $dir1
tar cvfz `date +%Y-%m`-${dir2_name} $dir2