backup copy

基本解释

So again, when the disk write completes, it is guaranteed to be both on the production and the backup copy.
所以，当磁盘写入完成后，可以保证同时在生产和备份副本上完成了写入。
Many open source solutions broadcast a backup copy of the session to every other node in the cluster each time it changes.
许多开放源码解决方案，每次在会话发生变化时，都把会话的备份拷贝广播到集群中的其他每个节点。
A database backup minimizes data loss and gives you the ability to reconstruct the failed database from the backup copy using the recovery process.
数据库备份可以最小化数据的损失并使您能够使用恢复进程从备份副本中重新构建错误的数据库。

You really need that because if you have only one copy of something, you don't have a backup; so, you can store the one copy separately.
你真的很需要这项发明,因为要是你只有一份的话，你就没有备份;,这样的话，你就可以将副本单独留存。
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Chances, are, however, you keep a backup copy of your operating system on an optical disc in the desk drawer, just in case.
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The goal, says Real Networks Vice President Jeff Chasen, is to do away with space-consuming discs and let users create a backup copy of their video collection.
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So, periodically, whenever network traffic permits, the endpoint and the cloud should have a handshake, during which the endpoint updates the cloud with a backup copy of any files unique to that endpoint.
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