Initially the system was offline for a number of days.

最初系统有几天没有联网。

《柯林斯英汉双解大词典》

Rules are stored outside of application logic, making it easy for a business person to add or modify the rules while not taking the system offline.

规则储存在应用程序逻辑所在的位置之外，这使得商业人员能够更加容易地增加或修改规则，而不需要使系统离线。

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The snapshot functionality was provided so that administrators could create consistent, integrated snapshots of an online (or offline) JFS2 file system.

快照功能能使管理员对在线(或离线)JFS2文件系统创建一致、集成的快照。

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In other words, if you choose to change cloud vendors or move to an offline system how do you get your data back?

FORBES: Is Your Data Safe In The Cloud?

The other is a batch-oriented, offline system, using the big data ecosystem tools and consisting of the questions and the resulting analysis about what users are doing with the data and how they interact with the system.

FORBES: LucidWorks: Bringing Search to Big Data

Examples of this are things like moving from Office to Google Docs, moving from an offline CRM system like ACT to Salesforce.com, or moving from the desktop version of QuickBooks to QuickBooks Online.

FORBES: Is Your Data Safe In The Cloud?