D-Link DGS-3224TGR - Switch, Руководство пользователя

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DGS-3224TGR Gigabit Ethernet Switch User’s Guide
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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.
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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.
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Connected and Working – This trap is sent when the Redundant Power Supply is connected and working.
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Disconnect or Malfunction – This trap is sent whenever the Redundant Power Supply malfunctions.
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MAC Notification – This trap indicates that the switch had learned a new MAC address.
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:
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Sending and receiving SNMP packets through the IP protocol.
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Collecting information about the status and current configuration of network devices.
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Modifying the configuration of network devices.
The DGS-3224TGR has a software program called an ‘agent’ that processes SNMP requests, but the user program that
makes the requests and collects the responses runs on a management station (a designated computer on the network). The
SNMP agent and the user program both use the UDP/IP protocol to exchange packets.