Ubuntu：使用 anacron 和 rsync 每月备份到外部驱动器

我的目标是每月将我的 ubuntu/home/目录备份到外部驱动器，将其连接到计算机后，我就可以在 中看到它/media/ironman/Elements。为此，我使用rsync。

外部驱动器并不总是挂载的，所以我制作了一个交互式脚本，当驱动器没有挂载时，它会提示我挂载驱动器。我想安排这个脚本，anacron因为我的笔记本电脑经常关机。我认为我的设置不起作用是因为交互式部分：当我从命令行运行脚本时，我自然可以在同一命令行中看到它的输出。但是，anacron 不是从命令行运行的。

这是脚本/home/ironman/scripts/backup_anacron.sh

#!/bin/bash

# Variables
SOURCE_DIR="/home/ironman"
TARGET_DIR="/media/ironman/Elements/backup_$(date +%Y%m%d)"
EXCLUDES="--exclude=\"lost+found\" --exclude=\".cache\""
RSYNC_CMD="rsync -a --info=progress2 $EXCLUDES $SOURCE_DIR/ $TARGET_DIR"


# Function to check if the drive is mounted
check_mount() {
    if grep -qs "/media/ironman/Elements " /proc/mounts; then
        echo "Backup drive is mounted."
        return 0
    else
        return 1
    fi
}

# Check whether backup drive has enough free space
check_space() {
    # Get available space on target drive in kilobytes
    available_space=$(df --output=avail "/media/ironman/Elements" | tail -1)
    # Get required space for the source directory in kilobytes
    required_space=$(du -sk "$SOURCE_DIR" | cut -f1)
    
    if [ "$available_space" -ge "$required_space" ]; then
        echo "Enough space on backup drive. Required: $required_space KB, Available: $available_space KB."
        return 0
    else
        echo "Not enough space on backup drive. Required: $required_space KB, Available: $available_space KB. Manual backup necessary"
        echo $RSYNC_CMD
        exit 1
    fi
}

# Initial check
check_mount
if [ $? -eq 1 ]; then

    # If the drive is not mounted, prompt the user
    echo "Please mount drive within one minute."

    # Wait for up to 60 seconds for the drive to be mounted
    for i in {1..60}; do
    
        # check every second if drive is mounted
        sleep 1
        check_mount
        if [ $? -eq 0 ]; then
        
            # if enough space available, execute rsync, else print error message
        check_space
        if [ $? -eq 0 ]; then
                eval $RSYNC_CMD
                exit 0 
            fi
        fi
    done
fi


# If the drive is still not mounted after 60 seconds, print an error message
if [ $? -eq 1 ]; then
    echo "Backup drive is not mounted. Could not backup /home/ironman/. Command for manual backup:"
    echo $RSYNC_CMD
    exit 1
fi

# if enough space available, execute rsync, else exit script
check_space
if [ $? -eq 0 ]; then
    eval $RSYNC_CMD
    exit 0
fi

我在末尾添加了以下行/etc/anacrontab：

@monthly 15 backup.monthly nice /home/ironman/scripts/backup_anacron.sh

当我强制运行每月任务时/usr/sbin/anacron -n -f cron.monthly，什么也没发生。我做错了什么？