Cisco WS-X6K-SUP1A-2GE-RF Software Guide - Page 643

Chapter 36 Configuring SNMP Understanding How SNMPv1 and SNMPv2c Works SNMP ifindex Persistence Feature The SNMP ifIndex persistence feature is always enabled. With the ifIndex persistence feature, the ifIndex value of the port and VLAN is always retained and used after the following occurrences: • Switch reboot • High-availability switchover • Software upgrade • Module reset • Module removal and insertion of the same type of module For Fast EtherChannel and Gigabit EtherChannel interfaces, the ifIndex value is only retained and used after a high-availability switchover. Understanding How SNMPv1 and SNMPv2c Works The components of SNMPv1 and SNMPv2c network management fall into three categories: • Managed devices (such as a switch) • SNMP agents and MIBs, including Remote Monitoring (RMON) MIBs, which run on managed devices • SNMP network management applications, such as CiscoWorks2000, which communicate with agents to get statistics and alerts from the managed devices. See the "Using CiscoWorks2000" section on page 36-6 for more information on CiscoWorks2000. Note An SNMP management application, together with the computer it runs on, is called a Network ManagementSystem (NMS). Using Managed Devices Catalyst 6000 family switches are managed devices that support SNMP network management with the following features: • SNMP traps (see the "Configuring SNMPv1 and SNMPv2c from the CLI" section on page 36-10) • RMON in the supervisor engine module software (see Chapter 37, "Configuring RMON") • RMON and RMON2 on an external SwitchProbe device Using SNMP Agents and MIBs SNMP network management uses these SNMP agent functions: • Accessing a MIB variable-This function is initiated by the SNMP agent in response to a request from the NMS. The agent retrieves the value of the requested MIB variable and responds to the NMS with that value. 78-13315-02 Catalyst 6000 Family Software Configuration Guide-Releases 6.3 and 6.4 36-5