由于周六要參加容器化培訓，需要Mac虛擬機環境，恰逢我新入手新mac電腦，故而需要重裝一個VirtualBox。
本想著簡單的事情三五分鐘就搞定的，足足用了一個晚上。

1. 使用安裝VirtualBox
   brew cask install virtualbox
   會提示：

   The install failed (The Installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance.)
   

2. 執行腳本(需要root權限)

#!/bin/bash

unload() {
        if [ `ps -ef | grep -c VirtualBox$` -ne 0 ]
        then
                echo "VirtualBox still seems to be running. Please investigate!!"
                exit 1;
        elif [ `ps -ef | grep -c [V]ir` -gt 0 ]
        then
                echo "Stopping running processes before unloading Kernel Extensions"
                ps -ef | grep [V]ir | awk '{print $2}' | xargs kill
        fi
        echo "Unloading Kernel Extensions"
        kextstat | grep "org.virtualbox.kext.VBoxUSB" > /dev/null 2>&1 && sudo kextunload -b org.virtualbox.kext.VBoxUSB
        kextstat | grep "org.virtualbox.kext.VBoxNetFlt" > /dev/null 2>&1 && sudo kextunload -b org.virtualbox.kext.VBoxNetFlt
        kextstat | grep "org.virtualbox.kext.VBoxNetAdp" > /dev/null 2>&1 && sudo kextunload -b org.virtualbox.kext.VBoxNetAdp
        kextstat | grep "org.virtualbox.kext.VBoxDrv" > /dev/null 2>&1 && sudo kextunload -b org.virtualbox.kext.VBoxDrv
}

load() {
        echo "Loading Kernel Extentions"
        sudo kextload "/Library/Application Support/VirtualBox/VBoxDrv.kext" -r "/Library/Application Support/VirtualBox/"
        sudo kextload "/Library/Application Support/VirtualBox/VBoxNetAdp.kext" -r "/Library/Application Support/VirtualBox/"
        sudo kextload "/Library/Application Support/VirtualBox/VBoxNetFlt.kext" -r "/Library/Application Support/VirtualBox/"
        sudo kextload "/Library/Application Support/VirtualBox/VBoxUSB.kext" -r "/Library/Application Support/VirtualBox/"
}

case "$1" in
        unload|remove)
                unload
                ;;
        load)
                load
                ;;
        *|reload)
                unload
                load
                ;;
esac

將其保存至shell腳本中直接運行。

3. 打開System Preferences → Security & Privacy → General
   
   image

點擊 Allow。
重點來了： 在macOS 10.13.4 版本中有bug，鼠標直接點擊不了Allow 按鈕，所以只能用Tab 鍵將focus移到Allow上面，按下空格。

4. 執行重新安裝命令
   brew cask reinstall virtualbox

大功告成！