linux shell实现目录的增量备份

auto_backup_system.sh 

#针对目录进行备份；每周1-6执行增量备份，每周日(值为：0 or 7)执行全备份

#!/bin/bash
#Automatic Backup Linux System Files
#By Author xiaoheiyaoshangtian
#2024/x/x

source_dir=($*)
target_dir=/tmp
year=$(date +%Y)
month=$(date +%m)
day=$(date +%d)
week=$(date +%u)
files=system_backup.tar.gz
code=$?

if [ -z $source_dir ];then
  echo -e "Please Enter File or Directory You Need to Backup:\n--------------------------------------------------\nExample    $0 /boot /etc ......"
  exit
fi

#determin whether the target directory exists
if [ ! -d $target_dir/$year/$month/$day ];then
  mkdir -p $target_dir/$year/$month/$day
  echo "This $target_dir/$year/$month/$day created successfully!"
fi

#exec full backup function command
full_backup()
{
  if [ "$week" -eq "0" ];then
    rm -rf $target_dir/snapshot
    cd $target_dir/$year/$month/$day
    tar -g $target_dir/snapshot -czvPf $files $(echo ${source_dir[@]})
    [ "$code" == "0" ]&&echo -e "---------------------------------------\nfull_backup system files backup successfully!"
  fi
}

#perform incremental backup function command
add_backup()
{
  cd $target_dir/$year/$month/$day
  if [ -f $target_dir/$year/$month/$day/$files ];then
    read -p "$files already exists,overwrite confirmation yes or no(default yes)?:" sure
    if [ "$sure" == "no" -o "$sure" == "n" -o "$sure" == "N" -o "$sure" == "NO" -o "$sure" ==  "No" ];then
      sleep 1
      exit 0
    fi
    if [ $week -ne "0" ];then
    cd $target_dir/$year/$month/$day
    tar -g $target_dir/snapshot -czvPf $$_$files $(echo ${source_dir[@]})
    [ "$code" == "0" ]&&echo -e "---------------------------------------\nadd_backup system files backup successfully!"
    fi
  else
    if [ $week -ne "0" ];then
    cd $target_dir/$year/$month/$day
    tar -g $target_dir/snapshot -czvPf $files $(echo ${source_dir[@]})
    [ "$code" == "0" ]&&echo -e "---------------------------------------\nadd_backup system files backup successfully!"
    fi
  fi 
}

full_backup
add_backup

验证：

[root@logstash ~]# sh auto_backup_system.sh
Please Enter File or Directory You Need to Backup:
--------------------------------------------------
Example    auto_backup_system.sh /boot /etc ......
[root@logstash ~]# 
[root@logstash ~]# sh auto_backup_system.sh /tmp
This /tmp/2024/06/21 created successfully!
tar: /tmp: Directory is new
tar: /tmp/.ICE-unix: Directory is new
tar: /tmp/.Test-unix: Directory is new
tar: /tmp/.X11-unix: Directory is new
tar: /tmp/.XIM-unix: Directory is new
tar: /tmp/.font-unix: Directory is new
tar: /tmp/2024: Directory is new
tar: /tmp/2024/06: Directory is new
tar: /tmp/2024/06/21: Directory is new
/tmp/
/tmp/.ICE-unix/
/tmp/.Test-unix/
/tmp/.X11-unix/
/tmp/.XIM-unix/
/tmp/.font-unix/
/tmp/2024/
/tmp/2024/06/
/tmp/2024/06/21/
/tmp/snapshot
/tmp/2024/06/21/system_backup.tar.gz
---------------------------------------
add_backup system files backup successfully!
[root@logstash ~]# 
[root@logstash ~]# sh auto_backup_system.sh /tmp
system_backup.tar.gz already exists,overwrite confirmation yes or no(default yes)?:no
[root@logstash ~]# 
[root@logstash ~]# sh auto_backup_system.sh /tmp
system_backup.tar.gz already exists,overwrite confirmation yes or no(default yes)?:
/tmp/
/tmp/.ICE-unix/
/tmp/.Test-unix/
/tmp/.X11-unix/
/tmp/.XIM-unix/
/tmp/.font-unix/
/tmp/2024/
/tmp/2024/06/
/tmp/2024/06/21/
/tmp/2024/06/21/2577_system_backup.tar.gz
---------------------------------------
add_backup system files backup successfully!
[root@logstash ~]#

[root@logstash tmp]# ls
2024  snapshot
[root@logstash tmp]# 
[root@logstash tmp]# cd 2024/
[root@logstash 2024]# cd 06/21/
[root@logstash 21]# ls
2577_system_backup.tar.gz  system_backup.tar.gz
[root@logstash 21]#