Chapter 18. GEOM: Modular Disk Transformation Framework

Written by Tom Rhodes.
Table of Contents
18.1. Synopsis
18.2. RAID0 - Striping
18.3. RAID1 - Mirroring
18.4. RAID3 - Byte-level Striping with Dedicated Parity
18.5. Software RAID Devices
18.6. GEOM Gate Network
18.7. Labeling Disk Devices
18.8. UFS Journaling Through GEOM

18.1. Synopsis

In FreeBSD, the GEOM framework permits access and control to classes, such as Master Boot Records and BSD labels, through the use of providers, or the disk devices in /dev. By supporting various software RAID configurations, GEOM transparently provides access to the operating system and operating system utilities.

This chapter covers the use of disks under the GEOM framework in FreeBSD. This includes the major RAID control utilities which use the framework for configuration. This chapter is not a definitive guide to RAID configurations and only GEOM-supported RAID classifications are discussed.

After reading this chapter, you will know:

  • What type of RAID support is available through GEOM.

  • How to use the base utilities to configure, maintain, and manipulate the various RAID levels.

  • How to mirror, stripe, encrypt, and remotely connect disk devices through GEOM.

  • How to troubleshoot disks attached to the GEOM framework.

Before reading this chapter, you should:

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