Location Of Device Nodes For Evms Storage Objects - Novell LINUX ENTERPRISE SERVER 10 SP2 - STORAGE ADMINISTRATION GUIDE 05-15-2009 Administration Manual

Term Description
Segment An ordered set of physically contiguous sectors on a single device. It is similar
to traditional disk partitions.
Region An ordered set of logically contiguous sectors that might or might not be
physically contiguous. The underlying mapping can be to logical disks, disk
segments, or other storage regions.
Feature A logically contiguous address space created from one or more disks,
segments, regions, or other feature objects through the use of an EVMS
(Feature Object, EVMS
feature.
Feature, EVMS Object)
Storage Object Any storage structure in EVMS that is capable of being a block device. Disks,
segments, regions, and feature objects are all storage objects.
Container A collection of devices that is managed as a single pool of storage.
(Storage Container) Private Storage Container: A storage container that is exclusively owned and
accessed by only one server.
Cluster Storage Container: A storage container managed by the Cluster
Resource Manager. It is accessible to all nodes of a cluster. An administrator
can configure the storage objects in the cluster container from any node in the
cluster. Cluster containers can be private, shared, or deported.
Volume A mountable storage object. Logical volumes can be EVMS volumes or
compatibility volumes.
(Logical Volume)
1.5 Location of Device Nodes for EVMS Storage
Objects
EVMS creates a unified namespace for the logical volumes on your system in the
directory. It detects the storage objects actually present on a system, and creates an appropriate
device node for each one, such as those shown in the following table.
Private: The cluster container is exclusively owned and accessed by only
one particular node of a cluster at any given time. The ownership can be
reassigned by failover policies or the administrator.
Shared: The cluster container is concurrently owned and accessed by all
nodes of a cluster. Shared containers are preferred for distributed
databases, clustered file systems, and cluster-aware applications that can
coordinate safe access to shared volumes.
Deported: The cluster container is not owned or accessed by any node of
the cluster.
EVMS Volume: Volumes that contain EVMS metadata and support all
EVMS features. Device nodes for EVMS volumes are stored in the
evms directory. For example:
Compatibility Volume: Volumes that are backward-compatible to other
volume managers. They do not contain EVMS metadata and cannot
support EVMS features.
/dev/evms/my_volume
/dev/
/dev/evms
Overview of EVMS 13