Information About RMON
RMON is disabled by default, and no events or alarms are configured in the switch.
All switches in the Cisco MDS 9000 Family support the following RMON functions (defined in RFC 2819):
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Alarm—Each alarm monitors a specific management information base (MIB) object for a specified interval. When the MIB object value exceeds a specified value (rising threshold), the alarm condition is set and only one event is triggered regardless of how long the condition exists. When the MIB object value falls below a certain value (falling threshold), the alarm condition is cleared. This allows the alarm to trigger again when the rising threshold is crossed again.
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Event—Determines the action to take when an event is triggered by an alarm. The action can be to generate a log entry, an SNMP trap, or both.
For agent and management information, see the Cisco MDS 9000 Family MIB Quick Reference.
For information on an SNMP-compatible network management station, see the System Management Configuration Guide, Cisco DCNM for SAN.
For SNMP security-related CLI configurations, see .
RMON Configuration Information
RMON is disabled by default and no events or alarms are configured in the switch. You can configure your RMON alarms and events by using the CLI or an SNMP-compatible network management station.
Tip |
We recommend an additional, generic RMON console application on the network management station (NMS) to take advantage of RMON's network management capabilities. Refer to the System Management Configuration Guide, Cisco DCNM for SAN. |
RMON Configuration Using Threshold Manager
RMON is disabled by default and no events or alarms are configured in the switch. You can configure your RMON alarms and events by using the CLI or by using Threshold Manager in Device Manager.
The Threshold Monitor allows you to trigger an SNMP event or log a message when the selected statistic goes over a configured threshold value. RMON calls this a rising alarm threshold. The configurable settings are as follows:
- Variable—The statistic you want to set the threshold value on.
- Value—The value of the variable that you want the alarm to trigger at. This value is the difference (delta) between two consecutive polls of the variable by Device Manager.
- Sample—The sample period (in seconds) between two consecutive polls of the variable. Select your sample period such that the variable does not cross the threshold value you set under normal operating conditions.
- Warning—The warning level used by Device Manager to indicate the severity of the triggered alarm. This is a DCNM-SAN and Device Manager enhancement to RMON.
Note |
To configure any type of RMON alarm (absolute or delta, rising or falling threshold) click More on the Threshold Manager dialog box. You should be familiar with how RMON defines these concepts before configuring these advanced alarm types. Refer to the RMON-MIB (RFC 2819) for information on how to configure RMON alarms. |
Note |
You must also configure SNMP on the switch to access RMON MIB objects. |
RMON Alarm Configuration Information
Threshold Manager provides a list of common MIB objects to set an RMON threshold and alarm on. The alarm feature monitors a specific MIB object for a specified interval, triggers an alarm at a specified value (rising threshold), and resets the alarm at another value (falling threshold).
You can also set an alarm on any MIB object. The specified MIB must be an existing SNMP MIB object in standard dot notation (1.3.6.1.2.1.2.2.1.14.16777216 16 16777216 for ifInOctets.167772161616777216).
Use one of the following options to specify the interval to monitor the MIB variable (ranges from 1 to 4294967295 seconds):
- Use the delta option to test the change between samples of a MIB variable.
- Use the absolute option to test each MIB variable directly.
- Use the delta option to test any MIB objects that are counters.
The range for the rising threshold and falling threshold values is -2147483647 to 2147483647.
Caution |
The falling threshold must be less than the rising threshold . |
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.