- Index
- Preface
- Overview
- Using the Command-Line Interface
- Getting Started with CMS
- Assigning the Switch IP Address and Default Gateway
- Managing Switch Stacks
- Clustering Switches
- Administering the Switch
- Configuring SDM Templates
- Configuring Switch-Based Authentication
- Configuring 802.1X Port-Based Authentication
- Configuring Interface Characteristics
- Configuring VLANs
- Configuring VTP
- Configuring Voice VLAN
- Configuring STP
- Configuring MSTP
- Configuring Optional Spanning-Tree Features
- Configuring IGMP Snooping and MVR
- Configuring Port-Based Traffic Control
- Configuring CDP
- Configuring UDLD
- Configuring SPAN and RSPAN
- Configuring RMON
- Configuring System Message Logging
- Configuring SNMP
- Configuring Network Security with ACLs
- Configuring QoS
- Configuring EtherChannels
- Configuring IP Unicast Routing
- Configuring HSRP
- Configuring IP Multicast Routing
- Configuring MSDP
- Configuring Fallback Bridging
- Troubleshooting
- Supported MIBs
- Working with the Cisco IOS File System, Configuration Files, and Software Images
- Unsupported Commands in Cisco IOS Release 12.1(14)EA1
Configuring RMON
This chapter describes how to configure Remote Network Monitoring (RMON) on the Catalyst 3750 switch. Unless otherwise noted, the term switch refers to a standalone switch and to a switch stack.
RMON is a standard monitoring specification that defines a set of statistics and functions that can be exchanged between RMON-compliant console systems and network probes. RMON provides you with comprehensive network-fault diagnosis, planning, and performance-tuning information.
Note For complete syntax and usage information for the commands used in this chapter, refer to the Cisco IOS Configuration Fundamentals Command Reference for Release 12.1.
This chapter consists of these sections:
Understanding RMON
RMON is an Internet Engineering Task Force (IETF) standard monitoring specification that allows various network agents and console systems to exchange network monitoring data. You can use the RMON feature with the Simple Network Management Protocol (SNMP) agent in the switch to monitor all the traffic flowing among switches on all connected LAN segments.
Figure 23-1 Remote Monitoring Example
The switch supports these RMON groups (defined in RFC 1757):
•Statistics (RMON group 1)—Collects Ethernet, Fast Ethernet, and Gigabit Ethernet statistics on an interface.
•History (RMON group 2)—Collects a history group of statistics on Ethernet, Fast Ethernet, and Gigabit Ethernet interfaces for a specified polling interval.
•Alarm (RMON group 3)—Monitors a specific management information base (MIB) object for a specified interval, triggers an alarm at a specified value (rising threshold), and resets the alarm at another value (falling threshold). Alarms can be used with events; the alarm triggers an event, which can generate a log entry or an SNMP trap.
•Event (RMON group 9)—Determines the action to take when an event is triggered by an alarm. The action can be to generate a log entry or an SNMP trap.
Because switches supported by this software release use hardware counters for RMON data processing, the monitoring is more efficient, and little processing power is required.
Configuring RMON
These sections describe how to configure RMON on your switch:
•Configuring RMON Alarms and Events (required)
•Collecting Group History Statistics on an Interface (optional)
•Collecting Group Ethernet Statistics on an Interface (optional)
Default RMON Configuration
RMON is disabled by default; no alarms or events are configured.
Only RMON 1 is supported on the switch.
Configuring RMON Alarms and Events
You can configure your switch for RMON by using the command-line interface (CLI) or an SNMP-compatible network management station. We recommend that you use a generic RMON console application on the network management station (NMS) to take advantage of RMON's network management capabilities. You must also configure SNMP on the switch to access RMON MIB objects. For more information, see "Configuring SNMP."
Beginning in privileged EXEC mode, follow these steps to enable RMON alarms and events. This procedure is required.
To disable an alarm, use the no rmon alarm number global configuration command on each alarm you configured. You cannot disable at once all the alarms that you configured. To disable an event, use the no rmon event number global configuration command. To learn more about alarms and events and how they interact with each other, refer to RFC 1757.
You can set an alarm on any MIB object. The following example configures RMON alarm number 10 by using the rmon alarm command. The alarm monitors the MIB variable ifEntry.20.1 once every 20 seconds until the alarm is disabled and checks the change in the variable's rise or fall. If the ifEntry.20.1 value shows a MIB counter increase of 15 or more, such as from 100000 to 100015, the alarm is triggered. The alarm in turn triggers event number 1, which is configured with the rmon event command. Possible events can include a log entry or an SNMP trap. If the ifEntry.20.1 value changes by 0, the alarm is reset and can be triggered again.
Switch(config)# rmon alarm 10 ifEntry.20.1 20 delta rising-threshold 15 1
falling-threshold 0 owner jjohnson
The following example creates RMON event number 1 by using the rmon event command. The event is defined as High ifOutErrors and generates a log entry when the event is triggered by the alarm. The user jjones owns the row that is created in the event table by this command. This example also generates an SNMP trap when the event is triggered.
Switch(config)# rmon event 1 log trap eventtrap description "High ifOutErrors" owner
jjones
Collecting Group History Statistics on an Interface
You must first configure RMON alarms and events to display collection information.
Beginning in privileged EXEC mode, follow these steps to collect group history statistics on an interface. This procedure is optional.
To disable history collection, use the no rmon collection history index interface configuration command.
Collecting Group Ethernet Statistics on an Interface
Beginning in privileged EXEC mode, follow these steps to collect group Ethernet statistics on an interface. This procedure is optional.
To disable the collection of group Ethernet statistics, use the no rmon collection stats index interface configuration command.
This example shows how to collect RMON statistics for the owner root on Gigabit Ethernet interface 0/1 of stack member 2:
Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# rmon collection stats 2 owner root
Displaying RMON Status
To display the RMON status, use one or more of the privileged EXEC commands in Table 23-1:
For information about the fields in these displays, refer to the Cisco IOS Configuration Fundamentals Command Reference for Release 12.1.