HP StorageWorks Fabric OS 5.0.0 MIB Reference Guide (AA-RW1QA-TE, May 2005)

122 Entity MIB objects
• Container: one entry for each FRU slot (one switch blade, two power supplies, six fans)
• Module: one entry for switch blade, up to two entries for power supplies, and up to six
entries for fans.
The SAN Switch 4/32 can have the following hierarchy of physical objects:
• Chassis: one entry (one row)
• Container: one entry for each FRU slot (one switch blade, two power supplies, three
fans)
• Module: one entry for switch blade, up to two entries for power supplies, and up to
three entries for fans.
entPhysicalParentRelPos
OID 1.3.6.1.2.1.47.1.1.1.1.6
Status Current
Description An indication of the relative position of this child component among all its sibling
components. Sibling components are defined as entPhysicalEntry, which shares the same
instance values of each of the entPhysicalContainedIn and entPhysicalClass objects.
Note For chassis entry, this value is –1; for containers, it is the sequential number of the
container from the first one; for all FRUs, it is always 1.
An NMS can use this object to identify the relative ordering for all sibling components of
a particular parent (identified by the entPhysicalContainedIn instance in each sibling
entry).
This value should match any external labeling of the physical component if possible. For
example, for a container (such as a card slot) labeled slot #3, entPhysicalParentRelPos
should have the value 3. Note that the entPhysicalEntry for the module plugged into slot 3
should have an entPhysicalParentRelPos value of 1.
If the physical position of this component does not match any external numbering or
clearly visible ordering, user documentation or other external reference material should
be used to determine the parent-relative position. If this is not possible, the agent should
assign a consistent (but possibly arbitrary) ordering to a given set of sibling components,
perhaps based on internal representation of the components.
If the agent cannot determine the parent-relative position for some reason, or if the
associated value of entPhysicalContainedIn is 0, then the value –1 is returned; otherwise,
a non-negative integer is returned, indicating the parent-relative position of this physical
entity.
Parent-relative ordering normally starts from 1 and continues to n, where n represents the
highest-positioned child entity. However, if the physical entities (for example, slots) are
labeled from a starting position of zero, then the first sibling should be associated with an
entPhysicalParentRelPos value of 0. Note that this ordering may be sparse or dense,
depending on agent implementation.
The actual values returned are not globally meaningful, as each parent component may
use different numbering algorithms. The ordering is meaningful only among siblings of
the same parent component.
The agent should retain parent-relative position values across reboots, either through
algorithmic assignment or use of nonvolatile storage.