In addition to managing LLC-based token-ring networks, LAN Network Manager also manages token-ring networks that communicate through the Simple Network Management Protocol (SNMP). LAN Network Manager uses two of its applications, the SNMP bridge application and the SNMP token-ring application, to manage the token-ring segments in the networks and the SNMP devices that interconnect them.
The SNMP token-ring application reports dynamic status changes on the token-ring network and enables LAN Network Manager to retrieve station information and set management parameters. LAN Network Manager receives its configuration information about the token-ring resources from the following SNMP proxy agents:
The SNMP bridge application provides LAN Network Manager with the management of the SNMP bridging devices and shows the connectivity of the bridges to other environments, such as X.25, Frame Relay, Ethernet, and FDDI. The SNMP bridge application notifies LAN Network Manager of status changes in the SNMP bridges and relays management instructions from LAN Network Manager to the bridges.
LAN Network Manager manages several types of bridges through the SNMP bridge application:
The SNMP bridge application obtains resource information from agent resources that implement the RFC 1286 and RFC 1213 (MIB II) MIBs (or the RFC 1493 and 1213 MIBs), along with other MIBs.
LAN Network Manager communicates with several agent resources in the SNMP token-ring networks to retrieve configuration information and to send management instructions to stations. These agents vary depending on whether the information pertains to a segment or station or to an SNMP bridge.
Token-ring segment information is acquired from the following kinds of agents:
Sometimes the value of a parameter displayed in a window is simultaneously reported by more than one agent. When this happens, LAN Network Manager displays the value from the agent MIB according to the following priority scheme, beginning with the highest priority agent: token-ring surrogate agent, remote-monitor agent, and concentrator agent.
The reporting agent can change when other agents are discovered. For example, if a remote-monitor agent is discovered first, LAN Network Manager displays the value provided by the RMON agent until a surrogate agent is discovered. Management of the segment then shifts to the surrogate agent.
Also, using SMIT you can disable the automatic priority scheme used by LAN Network Manager. By specifying whether or not you want an agent to be discovered, you can change the agent that has the highest priority. For more information, refer to the section describing the Manage the agent parameter in Configuring SNMP Agents that Manage Token-Ring Segments.
LAN Network Manager manages SNMP bridges through agents that are resident in the bridging devices. LAN Network Manager supports those agents that implement either RFC 1286 and RFC 1213 (MIB II), or RFC 1213 (MIB II) and RFC 1493. LAN Network Manager can also provide information from agents that support the following MIBs: