Mibs; Snmp - D-Link DGS-3224TG User Manual

from a factory reset in that configuration settings saved to non-volatile RAM used to
reconfigure the switch.
•
Authentication Failure – This trap signifies that someone has tried to logon to the switch
using an invalid SNMP community string. The switch automatically stores the source IP
address of the unauthorized user.
•
New Root – This trap indicates that the switch has become the new root of the Spanning Tree,
the trap is sent by the switch soon after its election as the new root. This implies that upon
expiration of the Topology Change Timer the new root trap is sent out immediately after the
switch's election as the new root.
•
Topology Change (STP) – A Topology Change trap is sent by the switch when any of its
configured ports transitions from the Learning state to the Forwarding state, or from the
Forwarding state to the Blocking state. The trap is not sent if a new root trap is sent for the
same transition.

MIBs

Management and counter information are stored in the switch in the Management Information Base
(MIB). The switch uses the standard MIB-II Management Information Base module. Consequently,
values for MIB objects can be retrieved from any SNMP-based network management software. In
addition to the standard MIB-II, the switch also supports its own proprietary enterprise MIB as an
extended Management Information Base. These MIBs may also be retrieved by specifying the MIB's
Object-Identity (OID) at the network manager. MIB values can be either read-only or read-write.
Read-only MIBs variables can be either constants that are programmed into the switch, or variables
that change while the switch is in operation. Examples of read-only constants are the number of port
and type of ports. Examples of read-only variables are the statistics counters such as the number of
errors that have occurred, or how many kilobytes of data have been received and forwarded through a
port.
Read-write MIBs are variables usually related to user-customized configurations. Examples of these are
the switch's IP Address, Spanning Tree Algorithm parameters, and port status.
If you use a third-party vendors' SNMP software to manage the switch, a diskette listing the switch's
propriety enterprise MIBs can be obtained by request. If your software provides functions to browse or
modify MIBs, you can also get the MIB values and change them (if the MIBs' attributes permit the write
operation). This process however can be quite involved, since you must know the MIB OIDs and retrieve
them one by one.

SNMP

The Simple Network Management Protocol (SNMP) is an OSI layer 7 (the application layer) protocol for
remotely monitoring and configuring network devices. SNMP enables network management stations to
read and modify the settings of gateways, routers, switches, and other network devices. SNMP can be
used to perform many of the same functions as a directly connected console, or can be used within an
integrated network management software package such as HP OpenView or DView.
SNMP performs the following functions:
•
Sending and receiving SNMP packets through the IP protocol.
DGS-3224TG Gigabit Ethernet Switch User's Guide
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