But that's okay, I had a backup.
没关系，我有备份！
Just to be sure I kicked off an extra backup and once done did a test boot using the external drive to ensure I had an easy return path to Snow Leopard if things went badly wrong.
我只是要确定，我所开始的这次额外备份在其完成之后，会使用外部驱动来进行一次测试启动，这就确保了如果事情出现了严重错误的话，我会有一种很容易就返回到Snow Leopard中的手段。
In six months of using SuperMemo, I had to restore from a full backup three times, each time losing six to eight hours of work.
在六个月的使用期类，我做过三次完整恢复，每一次恢复都让我损失六到八个小时的工作。
Always backup your code - I've experienced a complete hard drive failue and lost a lot of code when I was younger and felt horrible because of what had happened.
经常备份代码。 在我年轻时，我就有过因硬盘故障而丢了大量代码的经历，这经历很恐怖的。
Before attempting a major OS upgrade I first made sure I had a bootable backup of my current Snow Leopard install on an external firewire drive.
在打算进行有较大风险的OS升级之前，我先确保自己当前的Snow Leopard有一个安装在外部火线驱动器上的可启动的备份。
Before attempting a major OS upgrade I first made sure I had a bootable backup of my current Snow Leopard install on an external firewire drive.
在打算进行有较大风险的OS升级之前，我先确保自己当前的Snow Leopard有一个安装在外部火线驱动器上的可启动的备份。
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