Observer Analyzer : Observer Analyzer : SNMP Management Console : Using SNMP Management Console
Using SNMP Management Console
The SNMP Management Console is integrated into the Observer interface. Make certain that you have the SNMP Management Console Agent List visible.
When Observer is licensed to include SNMP Management Console, the Console is running at all times. To view the Console windows, just click on one of the SNMP agents in the List of SNMP Agents.
When an agent is selected, Observer’s interface turns into the SNMP Management Console interface. You will notice that the menus, button bars, and main display areas change. You can return to the Observer interface by selecting a probe from the List of Probes.
The SNMP Management Console interface is divided into three main sections:
List of SNMP Agents pane—displays each agent as an icon. Agents are queried by request files that define five types of requests: charts, forms, lists, tables, and traps. When an agent is selected, the requests are displayed in the SNMP Agent Requests pane.
SNMP Agent Request pane—SNMP Agent Requests are shown in this pane. Selecting a chart, form, list, table, or trap will display the associated request output in the Agent Display pane.
Agent Display pane—all data is displayed in one window per agent. Each item (charts, forms, lists, tables, and traps) is selected by the associated tab at the bottom of the Agent window.
Additionally, SNMP agents can be displayed in map format alongside of Observer probes. The map format lets you display graphically (either geographically or topologically) your network layout, including the positions of SNMP agents and the connections between them and Observer probes. You can scan in or draw a map or diagram and place your servers, hosts, and other SNMP agents in their appropriate locations. SNMP Management Console includes a set of bitmaps for different devices, or you may add your own bitmaps for map objects (in Windows BMP format).
SNMP Management Console lets you add, edit, or delete agent entries. When you add a new agent entry, you must associate a request file with it. Assigning a MIB also makes available a set of preconfigured menu requests used to poll the agent for data. A request file defines a set of objects for monitoring from one or more MIB groups. You can remove request items or create and add new request items using the MIB Editor.
SNMP Management Console polls SNMP agents and displays the collected information in a chart, form, list, or table. To accomplish this, the SNMP Management Console creates request packets in SNMP format and sends these packets to agents using the UDP protocol as the carrier. The SNMP packet, often called a PDU (Protocol Data Unit), consists of one or more SNMP objects.
When SNMP Management Console sends an SNMP packet to an SNMP agent, it either asks for information about an object (a Get request), or asks to set the value of an object (a Set request). When the agent receives the SNMP packet, it checks whether the object exists in the agent's MIB, finds object values, creates a reply packet, and returns the reply packet to the SNMP Management Console.
Because SNMP uses UDP (User Datagram Protocol) to transfer requests and replies, and because the UDP protocol does not require the receiving station to acknowledge receipt of a packet, there is a chance that either the request or reply packet will be lost.
To address this potential problem, SNMP Management Console uses a timeout-retry mechanism. You can specify the amount of time SNMP Management Console will wait before deciding that the request was lost and the number of times SNMP Management Console will resend the packet. When the maximum number of retries is reached and no reply has been received, SNMP Management Console considers the SNMP agent not present, out of order, or turned off, and displays a timed out message in the agent log.