This avoids any downtime that can occur during a full upgrade maintenance cycle.

这避免了在全面的升级维护过程中发生停机。

youdao

Finally, we believe that a fully integrated and feature-full upgrade mechanism should exist to allow end users and system operators of all walks of life to easily maintain their systems.

最终，我们相信一个高度集成的，优秀的且易于升级的系统架构的出现，可以让用户和系统管理员不再为如何维护自己的系统而伤透脑筋。

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

The gaming industry tends to upgrade equipment in seven year cycles. 2001 was the last full upgrade cycle.

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The big question, however, is whether Apple will choose to release a full upgrade (like the iPhone 3, 4 or 5) or simply enhance the existing model (similar to the iPhone 3GS and 4S).

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Separately, the board decided that it will switch to a rolling release model, in which users won't have to do a full system upgrade to take advantage of major OS updates.

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