D-Link DGS-1510-10L/ME, Руководство по установке оборудования

Страница: 37 / 67

DGS-1510/ME Series Metro Ethernet Switch Hardware Installation Guide
32
SNMP Settings
The Simple Network Management Protocol (SNMP) is an OSI Layer 7 (Application Layer) designed specifically for
managing and monitoring network devices. SNMP enables network management stations to read and modify the
settings of gateways, routers, switches and other network devices. Use SNMP to configure system features for proper
operation, monitor performance and detect potential problems in the Switch, switch group or network.
Managed devices that support SNMP include software (referred to as an agent), which runs locally on the device. A
defined set of variables (managed objects) is maintained by the SNMP agent and used to manage the device. These
objects are defined in a Management Information Base (MIB), which provides a standard presentation of the
information controlled by the on-board SNMP agent. SNMP defines both the format of the MIB specifications and the
protocol used to access this information over the network.
The Switch supports SNMP versions 1, 2c, and 3. The administrator may specify which SNMP version to use to
monitor and control the Switch. The three SNMP versions vary in the level of security provided between the
management station and the network device.
In SNMPv1 and SNMPv2c, user authentication is accomplished using 'community strings', which function like
passwords. The remote user SNMP application and the Switch SNMP must use the same community string. SNMP
packets from any station that has not been authenticated are ignored (dropped).
The default community strings for the Switch used for SNMPv1 and SNMPv2c management access are:
•
public - Allows authorized management stations to retrieve MIB objects.
•
private - Allows authorized management stations to retrieve and modify MIB objects.
SNMPv3 uses a more sophisticated authentication process that is separated into two parts. The first part is to
maintain a list of users and their attributes that are allowed to act as SNMP managers. The second part describes
what each user on that list can do as an SNMP manager.
The Switch allows groups of users to be listed and configured with a shared set of privileges. The SNMP version may
also be set for a listed group of SNMP managers. Thus, a group of SNMP managers can be created to view read-only
information or receive traps using SNMPv1 while assigning a higher level of security to another group, granting
read/write privileges using SNMPv3.
Using SNMPv3 individual users or groups of SNMP managers can be allowed to perform or be restricted from
performing specific SNMP management functions. The functions allowed or restricted are defined using the Object
Identifier (OID) associated with a specific MIB. An additional layer of security is available for SNMPv3 in that SNMP
messages may be encrypted.
Traps
Traps are messages that alert network personnel of events that occur on the Switch. The events can be as serious as
a reboot (someone accidentally turned OFF the Switch), or less serious like a port status change. The Switch
generates traps and sends them to the trap recipient (or network manager). Typical traps include trap messages for
Authentication Failure, Topology Change and Broadcast\Multicast Storm.
Management Information Base (MIB)
The Switch in the Management Information Base (MIB) stores management and counter information. The Switch uses
the standard MIB-II 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. The proprietary MIB may also be retrieved by specifying the MIB’s
Object Identifier. MIB values can be either read-only or read-write.