backup copy

基本解釋

So again, when the disk write completes, it is guaranteed to be both on the production and the backup copy.
所以，當(dāng)磁盤寫入完成后，可以保證同時(shí)在生產(chǎn)和備份副本上完成了寫入。
Many open source solutions broadcast a backup copy of the session to every other node in the cluster each time it changes.
許多開放源碼解決方案，每次在會(huì)話發(fā)生變化時(shí)，都把會(huì)話的備份拷貝廣播到集群中的其他每個(gè)節(jié)點(diǎn)。
A database backup minimizes data loss and gives you the ability to reconstruct the failed database from the backup copy using the recovery process.
數(shù)據(jù)庫備份可以最小化數(shù)據(jù)的損失并使您能夠使用恢復(fù)進(jìn)程從備份副本中重新構(gòu)建錯(cuò)誤的數(shù)據(jù)庫。

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.
你真的很需要這項(xiàng)發(fā)明,因?yàn)橐悄阒挥幸环莸脑挘憔蜎]有備份;,這樣的話，你就可以將副本單獨(dú)留存。
耶魯公開課 - 金融市場課程節(jié)選

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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