Chapter 20. GEOM: Modular Disk Transformation Framework

Written by Tom Rhodes.
Table of Contents
20.1. Synopsis
20.2. GEOM Introduction
20.3. RAID0 - Striping
20.4. RAID1 - Mirroring
20.5. Software RAID Devices
20.6. RAID3 - Byte-level Striping with Dedicated Parity
20.7. GEOM Gate Network Devices
20.8. Labeling Disk Devices
20.9. UFS Journaling Through GEOM

20.1. Synopsis

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 will not go into in depth discussion on how GEOM handles or controls I/O, the underlying subsystem, or code. This information is provided in geom(4) and its various SEE ALSO references. This chapter is also not a definitive guide to RAID configurations and only GEOM-supported RAID classifications will be 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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