Feedback
Contents
Configuring RMON
This chapter contains the following sections:
Configuring RMON
Information About 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. The Cisco NX-OS supports RMON alarms, events and logs to monitor Cisco Nexus 5000 Series switches
An RMON alarm monitors a specific management information base (MIB) object for a specified interval, triggers an alarm at a specified threshold value (threshold), and resets the alarm at another threshold value. You can use alarms with RMON events to generate a log entry or an SNMP notification when the RMON alarm triggers.
RMON is disabled by default and no events or alarms are configured in Cisco Nexus 5000 Series. You can configure your RMON alarms and events by using the CLI or an SNMP-compatible network management station
RMON Alarms
You can set an alarm on any MIB object that resolves into an SNMP INTEGER type. The specified object must be an existing SNMP MIB object in standard dot notation (for example, 1.3.6.1.2.1.2.2.1.17 represents ifOutOctets.17).
When you create an alarm, you specify the following parameters:
MIB object to monitor
Sampling interval—The interval that the Cisco Nexus 5000 Series switch uses to collect a sample value of the MIB object.
The sample type—Absolute samples take the current snapshot of the MIB object value. Delta samples take two consecutive samples and calculate the difference between them.
Rising threshold—The value at which the Cisco Nexus 5000 Series switch triggers a rising alarm or resets a falling alarm.
Falling threshold—The value at which the Cisco Nexus 5000 Series switch triggers a falling alarm or resets a rising alarm.
Events—The action that the Cisco Nexus 5000 Series switch takes when an alarm (rising or falling) triggers.
Note
Use the hcalarms option to set an alarm on a 64-bit integer MIB object.
For example, you can set a delta type rising alarm on an error counter MIB object. If the error counter delta exceeds this value, you can trigger an event that sends an SNMP notification and logs the rising alarm event. This rising alarm will not occur again until the delta sample for the error counter drops below the falling threshold.
Note
The falling threshold must be less than the rising threshold.
RMON Events
You can associate a particular event to each RMON alarm. RMON supports the following event types:
SNMP notification—Sends an SNMP risingAlarm or fallingAlarm notification when the associated alarm triggers.
Log—Adds an entry in the RMON log table when the associated alarm triggers.
Both—Sends an SNMP notification and adds an entry in the RMON log table when the associated alarm triggers.
You can specify a different even for a falling alarm and a rising alarm.
Configuring RMON
Configuring RMON Alarms
ProcedureYou can configure RMON alarms on any integer-based SNMP MIB object.
You can optionally specify the following parameters:
The event-number to trigger if the rising or falling threshold exceeds the specified limit.
The owner of the alarm.
Ensure you have configured an SNMP user and enabled SNMP notifications.
The following example shows how to configure RMON alarms:
switch# configure terminalswitch(config)# rmon alarm 1 1.3.6.1.2.1.2.2.1.17.83886080 5 delta rising-threshold 5 1 falling-threshold 0 owner testswitch(config)# exitswitch# show rmon alarmsAlarm 1 is active, owned by testMonitors 1.3.6.1.2.1.2.2.1.17.83886080 every 5 second(s)Taking delta samples, last value was 0Rising threshold is 5, assigned to event 1Falling threshold is 0, assigned to event 0On startup enable rising or falling alarmConfiguring RMON Events
ProcedureYou can configure RMON events to associate with RMON alarms. You can reuse the same event with multiple RMON alarms.
Ensure you have configured an SNMP user and enabled SNMP notifications.
