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。

youdao

Finally, with full system replication, you can't take advantage of the high availability environment to reduce OS upgrade outages, or for less disruptive hardware maintenance.

最后，使用全系统复制，就不能利用高可用性环境的优势来缩短操作系统升级导致的中断时间或减少毁灭性硬件维护。

youdao

Administration: servers, and in particular software, requires continuous upkeep such as installation of security patches, upgrade of the OS and middleware, user account management and so on.

管理：服务器和某些软件需要连续维护，比如安装安全补丁、升级操作系统和中间件、用户账号管理等等。

youdao

The market could receive a significant boost in October when Microsoft (NASDAQ: MSFT) releases its highly anticipated OS upgrade, Windows 8.

FORBES: Did Apple or the Economy Cause the PC Sales Slump?

Whether that's a lot or a little depends entirely on your frame of reference -- after all, four million copies of the OS upgrade were sold in the first four days.

ENGADGET: Start button utility strips even more '8' from Windows 8, has sold 'tens of thousands' of copies

With the Ice Cream Sandwich OS upgrade, Samsung offered innovative new features such as Shape Match and Formula Match, providing a new way for organizing and expressing ideas in their personal and professional life.

ENGADGET: Samsung Galaxy Note II unveiled: 5.5-inch HD Super AMOLED display, Android Jelly Bean and more S Pen functionality