You must create two disk partitions on the SD card.

必须在sd卡上创建两个磁盘分区。

youdao

Each metadevice is built from slices in the actual physical disk partitions.

每个metadevice都是由实际的物理磁盘分区中的片构成的。

youdao

The main difficulty is that low-level management of disk partitions risks system integrity, if anything goes wrong.

主要困难在于，如果任何事情发生错误，那么磁盘分区的低级管理将危及系统完整性。

youdao

Many observers have suggested defensive techniques that deploy TrueCrypt disk encryption with hidden volume partitions or PGP Whole Disk Encryption rendering the entire computer unbootable thereby making even file time and date stamps unavailable.

FORBES: Move up http://i.forbesimg.com t Move down

Never mind that this is mostly pointless: if the hard disk crashes, both partitions are lost.

FORBES: With Rise Of Consumer Mobile Devices, We're All CIOs Now