HP-UX I/O Subsystem EVM Events

1 Introduction
The HP-UX I/O subsystem uses the Event management system (EVM) mechanism to report changes in I/O
components’ state. The EVM subsystem provides services to distribute, store and retrieve this information. This
document provides the details of the EVM events generated by the I/O subsystem. It covers the circumstances
during which the event is generated, the format of the events, and the information contained in the event. A
generic example of the EVM subsystem is also provided.
The document is intended for use by the subscribers of the EVM events. One such subscriber to I/O subsystem
generated EVM events is the setboot command.
2 I/O Terms and Definitions
The following table contains the I/O terms and definitions that are used in the document.
Terms Definitions
I/O node A component in the I/O tree that corresponds to a physical or virtual device.
I/O Tree
A runtime kernel I/O data structure on system’s device configuration. There are two
views of the I/O Tree in HP-UX 11i v3: legacy I/O view and agile I/O view.
Legacy I/O Node
A component in the I/O Tree representing a physical or virtual I/O device in the
legacy view.
Agile I/O Node
A component in the I/O Tree representing a physical or virtual I/O device in the
agile view.
Stale I/O Node
A stale node corresponds to the entries that are present in the I/O configuration file
but a corresponding device is not found.
Class Set of I/O nodes that fall under the same category of devices, such as disk class or
tape class.
Instance A uniquely assigned number of an I/O node within a class.
Device Special File (DSF) A special file used to communicate with a device driver.
EVM Event Management System.
Hardware Path Each I/O node is assigned a hardware address that is unique to the node. The
hardware path is a sequence of I/O nodes that share a hierarchical relationship.
Legacy Hardware Path Hardware path of an I/O node in the legacy view of the I/O tree.
Agile Hardware Path Hardware path of an I/O node in the agile view of the I/O tree.
Property of I/O node A property is a name and the data value associated with the I/O node.
WBEM
Web-Based Enterprise Management. An industry-wide standards-based initiative to
aid the management of large scale systems
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