Indeed, the alt_disk_copy is often used to clone the rootvg to a spare disk for regular on-line backup of rootvg.

对于 rootvg 的定期在线备份，常常使用 alt_disk_copy 把 rootvg 克隆到空闲磁盘上。

youdao

Better on-time performance, for instance, requires spare planes, backup crews, extra mechanics on duty, and so on.

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