An enumerated value which provides an indication of the
general hardware type of a particular physical entity.
There are no restrictions as to the number of
entPhysicalEntries of each entPhysicalClass, which must be
instantiated by an agent.
The enumeration 'other' is applicable if the physical entity
class is known, but does not match any of the supported
values.
The enumeration 'unknown' is applicable if the physical
entity class is unknown to the agent.
The enumeration 'chassis' is applicable if the physical
entity class is an overall container for networking
equipment. Any class of physical entity, except a stack,
may be contained within a chassis; and a chassis may only
be contained within a stack.
The enumeration 'backplane' is applicable if the physical
entity class is some sort of device for aggregating and
forwarding networking traffic, such as a shared backplane in
a modular ethernet switch. Note that an agent may model a
backplane as a single physical entity, which is actually
implemented as multiple discrete physical components (within
a chassis or stack).
The enumeration 'container' is applicable if the physical
entity class is capable of containing one or more removable
physical entities, possibly of different types. For
example, each (empty or full) slot in a chassis will be
modeled as a container. Note that all removable physical
entities should be modeled within a container entity, such
as field-replaceable modules, fans, or power supplies. Note
that all known containers should be modeled by the agent,
including empty containers.
The enumeration 'powerSupply' is applicable if the physical
entity class is a power-supplying component.
The enumeration 'fan' is applicable if the physical entity
class is a fan or other heat-reduction component.
The enumeration 'sensor' is applicable if the physical
entity class is some sort of sensor, such as a temperature
sensor within a router chassis.
The enumeration 'module' is applicable if the physical
entity class is some sort of self-contained sub-system. If
the enumeration 'module' is removable, then it should be
modeled within a container entity, otherwise it should be
modeled directly within another physical entity (e.g., a
chassis or another module).
The enumeration 'port' is applicable if the physical entity
class is some sort of networking port, capable of receiving
and/or transmitting networking traffic.
The enumeration 'stack' is applicable if the physical entity
class is some sort of super-container (possibly virtual),
intended to group together multiple chassis entities. A
stack may be realized by a 'virtual' cable, a real
interconnect cable, attached to multiple chassis, or may in
fact be comprised of multiple interconnect cables. A stack
should not be modeled within any other physical entities,
but a stack may be contained within another stack. Only
chassis entities should be contained within a stack.
The enumeration 'cpu' is applicable if the physical entity
class is some sort of central processing unit.
PhysicalIndex
int32
An arbitrary value that uniquely identifies the physical
entity. The value should be a small, positive integer.
Index values for different physical entities are not
necessarily contiguous.
PhysicalIndexOrZero
int32
This textual convention is an extension of the
PhysicalIndex convention, which defines a greater than zero
value used to identify a physical entity. This extension
permits the additional value of zero. The semantics of the
value zero are object-specific and must, therefore, be
defined as part of the description of any object that uses
this syntax. Examples of the usage of this extension are
situations where none or all physical entities need to be
referenced.
SnmpEngineIdOrNone
binary
A specially formatted SnmpEngineID string for use with the
Entity MIB.
If an instance of an object of SYNTAX SnmpEngineIdOrNone has
a non-zero length, then the object encoding and semantics
are defined by the SnmpEngineID textual convention (see STD
62, RFC 3411 [RFC3411]).
If an instance of an object of SYNTAX SnmpEngineIdOrNone
contains a zero-length string, then no appropriate
SnmpEngineID is associated with the logical entity (i.e.,
SNMPv3 is not supported).