Table of Contents
Advertisement
Chapter 3. Operational Characteristics
This chapter describes the operational characteristics of the 3494 Tape Library.
3490E, 3590, and 3592 Tape Subsystem Operation
The 3494 Tape Library controls the loading, unloading, and associated operations
of its tape subsystems. No operator attendance is required unless the 3494 Tape
Library cannot recover from a subsystem problem.
In addition to existing tape subsystem error recovery, the control unit and the
Library Manager execute additional recovery procedures when the tape drive
detects a load, unload, or tension loss failure.
TS7700 Virtualization Engine Components
The TS7700 Virtualization Engine consists of several primary components that can
be described in terms of their system role or according to their technical functions.
See the IBM Virtualization Engine TS7700 Information Center at http://
publib.boulder.ibm.com/infocenter/ts7700ic/v1r0/index.jsp for complete details
about using the TS7700 Virtualization Engine.
Nodes, Clusters, and Grid
The TS7700 Virtualization Engine is built on a distributed node architecture. The
nodes perform either virtualization (vNode) or hierarchical data storage
management (hNode). The vNode presents the image of a virtual library(ies) and
virtual drives to a host system. It receives tape drive and library requests from the
host and processes them as real devices would. It also translates the tape requests
through a virtual drive and uses a file in a file system to represent the virtual tape
image. After a logical volume has been created or altered by the host system
through a vNode it resides in disk cache or on physical tape, where it is managed
by the hNode. The hNode is the only node that is aware of physical tape resources
and the relationships between the logical volumes and physical volumes. It is also
responsible for any replication of the logical volumes and their attributes across
site boundaries.
Based on the node architecture, a vNode or hNode can run on separate
virtualization hardware or be combined to run on the same virtualization
hardware. When a vNode and hNode are combined to run on the same
virtualization hardware, they are referred to collectively as a General Node, or
gNode. The TS7700 Virtualization Engine runs a gNode. See Figure 42 on page 60
for an illustration of the relationship between nodes.
© Copyright IBM Corp. 2001, 2008
59
Advertisement
Table of Contents
