Overview Of Evms; Benefits Of Evms; Plug-In Layers - Novell LINUX ENTERPRISE SERVER 10 SP2 - STORAGE ADMINISTRATION GUIDE 05-15-2009 Administration Manual

Overview of EVMS

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The Enterprise Volume Management System (EVMS) 2.5.5 management tool for Linux* is an
extensible storage management tool that integrates all aspects of volume management, such as disk
partitioning, the Logical Volume Manager (LVM), the Multiple-Disk (MD) manager for software
RAIDs, the Device Mapper (DM) for multipath I/O configuration, and file system operations.
Section 1.1, "Benefits of EVMS," on page 11
Section 1.2, "Plug-In Layers," on page 11
Section 1.3, "Supported File Systems," on page 12
Section 1.4, "Terminology," on page 12
Section 1.5, "Location of Device Nodes for EVMS Storage Objects," on page 13

1.1 Benefits of EVMS

EVMS provides the following benefits:
An open source volume manager
A plug-in framework for flexible extensibility and customization
Plug-ins to extend functionality for new or evolving storage managers
Support for foreign partition formats
Cluster-aware

1.2 Plug-In Layers

EVMS abstracts the storage objects in functional layers to make storage management more user-
friendly. The following table describes the current EVMS plug-in layers for managing storage
devices and file systems:
EVMS Plug-In Layers
Table 1-1
Storage Managers
Device
Segment
Description
Manages the physical and logical
devices
Manages the partitioning of
physical and logical devices into
smaller segments of free space.
Segment managers can be
stacked. For example, a cluster
segment can contain other
storage objects or volumes.
Plug-Ins
Device Mapper (DM)
Uses Device Mapper (DM)
Segment managers include DOS,
GPT, System/390* (S/390),
Cluster, BSD, Mac, and BBR
For more information, see
Section 4.1, "Understanding Disk
Segmentation," on page 35.
Overview of EVMS
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