(Creating a bootable USB installer)为最新的 macOS Catalina创建可引导的 USB 安装程序在很多方面都有帮助。您可能想要这样做的原因之一是因为它可以让您在Mac上进行更新的全新安装。另一个原因是您可以使用 macOS 可引导安装程序是当您拥有多台Mac(Macs)并且希望在所有 Mac 上安装相同的更新时。
通过使用单个USB安装程序，您无需在每台Mac(Macs)上下载更新。同一个USB驱动器可用于将所有Mac(Macs)升级到驱动器上可用的最新版本。
它只要求您拥有一个至少有 8GB 可用存储空间的 USB 驱动器。然后，您可以在Mac上的(Mac)终端(Terminal)应用程序中使用应用程序或一些命令将驱动器变成 macOS 安装程序。我们将在下面向您展示如何做到这两点。
在您的 Mac 上下载 macOS Catalina 更新(Download The macOS Catalina Update On Your Mac)
您要做的第一件事是在Mac上下载整个更新。然后，您将此下载的文件作为安装程序放在您的USB驱动器上。
- 启动Mac App Store并搜索并单击macOS Catalina。
- 单击以下屏幕上的下载以下载更新。(Download)
- 坐下(Sit)来，放松一下，等待更新在您的Mac上完成下载。
这是一个相当大的更新，可能需要一个小时左右才能在您的计算机上完全下载。下载时间还取决于您的互联网(Internet)速度有多快。
确保(Make)不要继续下载更新后打开的安装程序。
使用 Disk Creator 创建 macOS Catalina USB 安装程序(Create a macOS Catalina USB Installer Using Disk Creator)
为任何 macOS 更新（包括Catalina(Catalina) ）创建可引导安装程序的最简单方法之一是使用Disk Creator应用程序。这是一个简单的程序，允许您加载更新，然后基于该更新创建安装程序。
它具有图形用户界面，因此您无需使用任何命令。另外，请记住，该应用程序将清除存储在USB驱动器上的所有现有数据。在执行此过程之前，请(Make)确保您已备份重要文件。
- 前往Disk Creator网站并将软件包下载到您的Mac上。从下载的存档中提取(Extract)文件并启动主应用程序文件。
- 主应用程序界面上只有少数几个选项。您要配置的第一件事是安装程序的目标。单击(Click)顶部的下拉菜单并选择您的USB驱动器。
- 接下来，单击选择 macOS 安装程序(Choose a macOS installer)按钮以选择您已下载到Mac的 macOS (Mac)Catalina更新。
- 为应用提供USB驱动器和Catalina文件后，单击应用底部的“创建安装程序”按钮开始该过程。(Create Installer)
- 等待(Wait)几分钟以创建USB安装程序。完成后，您会在屏幕上看到一条成功消息。
用于安装 macOS Catalina的USB安装程序现已准备就绪。将它插入任何需要升级到此版本 macOS的(an upgrade to this version of the macOS)Mac(Macs)。
使用终端制作 macOS USB 安装程序(Use Terminal To Make A macOS USB Installer)
如果您是那种不信任第三方应用程序的用户，尤其是在安装整个操作系统时，您不必使用Disk Creator来创建安装程序。
您可以使用Mac上的(Mac)终端(Terminal)应用程序来创建USB安装程序，并且只需几个命令即可。同样(Again)，您只需要一个 8GB 或更大的USB驱动器和 macOS Catalina更新文件。
- 在 Mac 上打开终端(Terminal)应用程序，输入sudo，按Space，但暂时不要按 Enter。
- 启动 Finder 窗口，打开Applications文件夹，找到 macOS Catalina更新，右键单击该文件，然后选择显示包内容(Show Package Contents)的选项。
- 打开Contents文件夹，然后打开Resources。找到名为createinstallmedia的文件并将其拖放到终端(Terminal)窗口中。它将填写更新路径。
- 在终端窗口中，按Space，输入–volume，按Space ，然后将(Space)USB设备从Finder拖放到终端(Terminal)窗口。它将输入您的USB驱动器的完整路径。
- 点击Enter，因为它是一个 sudo 命令，系统会要求您输入密码。输入密码并继续。
- 按键盘上的y键并按Enter以擦除驱动器并将Catalina安装程序放在上面。
它将开始擦除您的 USB 驱动器(start erasing your USB drive)，然后将其变成可启动的安装程序。留出足够的时间来完成。只需(Just)留意您的终端(Terminal)窗口，您就会知道它何时完成创建安装程序。
如何使用 macOS Catalina USB 安装程序(How To Use The macOS Catalina USB Installer)
创建USB安装程序后，您就可以像我们一样兴奋地安装更新，您只需执行几个步骤，即可从安装程序启动您的Mac 。
您可以通过两种方式使用新创建的安装程序。
使用系统偏好设置从 USB 安装程序启动(Use System Preferences To Boot From USB Installer)
第一种方法是更改启动选项，以便您的Mac从USB安装程序而不是当前启动磁盘启动。
- 单击 Apple 徽标并选择System Preferences。
- 选择Startup Disk，选择您的 USB 驱动器并点击Restart。
您的Mac将重新启动，它会从Catalina安装(Catalina)程序(t)启动，让您执行操作系统的(ion of the operating system)完全全新安装(full clean installa)。
直接从 USB 安装程序启动(Boot Directly From The USB Installer)
此方法不需要您更改任何启动设置即可使用安装程序。
- 关闭你的 Mac。
- 打开 Mac 并按住Option键。
- 从列表中选择您的USB安装程序并继续安装。
然后，您将按照标准 macOS 安装步骤将您的Mac(Macs)升级到这个较新版本的操作系统。
How To Create a Bootable macOS Catalina USB Drive
Creating a bootable USB installer for the latest macOS Catalina helps in many ways. One of the reasons why you may want to do it is because it lets you do a clean installation of the update on your Mac. The other reason is you can use a macOS bootable installer is when you have multiple Macs and you wish to install the same update on all of them.
By having a single USB installer, you won’t have to download the update on each of your Macs. The same USB drive can be used to upgrade all of your Macs to the latest version available on the drive.
All it requires you to have is a USB drive with at least 8GB of memory space available on it. You can then either use an application or a few commands in the Terminal app on your Mac to turn your drive into a macOS installer. We show you how to do both below.
Download The macOS Catalina Update On Your Mac
The first thing you’ll want to do is download the entire update on your Mac. You’ll then put this downloaded file as an installer on your USB drive.
- Launch the Mac App Store and search for and click on macOS Catalina.
- Click on Download on the following screen to download the update.
- Sit back, relax, and wait for the update to finish downloading on your Mac.
It’s quite a large update and will probably take an hour or so to fully download on your machine. The download time also depends on how fast your Internet speed is.
Make sure not to proceed with the installer that opens after the update is downloaded.
Create a macOS Catalina USB Installer Using Disk Creator
One of the easiest ways to create a bootable installer for any macOS update, including Catalina, is to use the Disk Creator app. It’s a simple program that allows you to load your update and then create an installer based on that update.
It has a graphical user interface so you don’t need to play around with any commands. Also, keep in mind that the app will erase all the existing data stored on the USB drive. Make sure you’ve backed up your important files before you do the procedure.
- Head over to the Disk Creator website and download the package to your Mac. Extract files from the downloaded archive and launch the main application file.
- There are only a handful of options on the main app interface. The first thing you’ll want to configure is the destination for the installer. Click on the dropdown at the top and select your USB drive.
- Next up, click on the Choose a macOS installer button to choose the macOS Catalina update you’ve downloaded to your Mac.
- Once you’ve given the app both your USB drive and your Catalina file, click on the Create Installer button at the bottom of the app to begin the process.
- Wait for a few minutes for the USB installer to be created. When it’s done, you’ll see a success message on your screen.
Your USB installer to install macOS Catalina is now ready. Plug it into any of your Macs that need an upgrade to this version of the macOS.
Use Terminal To Make A macOS USB Installer
If you’re the kind of user who doesn’t trust third-party apps, especially when installing entire operating systems, you don’t necessarily have to use Disk Creator to create the installer.
You can use the Terminal app on your Mac to create the USB installer and that too with just a few commands. Again, all that you’re going to need is an 8GB or larger USB drive and the macOS Catalina update file.
- Open the Terminal app on your Mac, type in sudo, press Space, but don’t hit Enter just yet.
- Launch a Finder window, open the Applications folder, find the macOS Catalina update, right-click on the file, and select the option that says Show Package Contents.
- Open the Contents folder followed by Resources. Find the file named createinstallmedia and drag and drop it onto your Terminal window. It’ll fill in the update path.
- In the Terminal window, press Space, type in –volume, press Space, and drag and drop your USB device from the Finder onto the Terminal window. It’ll enter the full path of your USB drive.
- Hit Enter and since it’s a sudo command, you’ll be asked to enter your password. Enter the password and proceed.
- Press the y key on your keyboard and hit Enter to erase the drive and put your Catalina installer on it.
It’ll start erasing your USB drive to then turn it into a bootable installer. Allow it a good amount of time to finish. Just keep an eye on your Terminal window and you’ll know when it finishes creating the installer.
How To Use The macOS Catalina USB Installer
Once a USB installer is created and you’ve got as much excitement to install the update as we do, you’ll just need to follow a few steps so your Mac boots from your installer.
There are two ways you can use your newly created installer.
Use System Preferences To Boot From USB Installer
The first method is to change a startup option so your Mac boots from the USB installer instead of your current boot disk.
- Click on the Apple logo and select System Preferences.
- Select Startup Disk, choose your USB drive and hit Restart.
Your Mac will reboot and it’ll boot up from your Catalina installer letting you perform a full clean installation of the operating system.
Boot Directly From The USB Installer
This method doesn’t require you to change any startup settings to use the installer.
- Power off your Mac.
- Turn your Mac on and hold down the Option key.
- Select your USB installer from the list and proceed with the installation.
You’ll then follow the standard macOS installation steps to upgrade your Macs to this newer version of the operating system.
