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Related Documentation
Understanding RMON Alarms
An RMON alarm identifies:
- A specific MIB object that is monitored.
- The frequency of sampling.
- The method of sampling.
- The thresholds against which the monitored values are compared.
An RMON alarm can also identify a specific eventTable entry to be triggered when a threshold is crossed.
Configuration and operational values are defined in alarmTable in RFC 2819. Additional operational values are defined in Juniper Networks enterprise-specific extensions to alarmTable (jnxRmonAlarmTable).
This topic covers the following sections:
alarmTable
alarmTable in the RMON MIB allows you to monitor and poll the following:
- alarmIndex—The index value for alarmTable that identifies a specific entry.
- alarmInterval—The interval, in seconds, over which data is sampled and compared with the rising and falling thresholds.
- alarmVariable—The MIB variable that is monitored by the alarm entry.
- alarmSampleType—The method of sampling the selected variable and calculating the value to be compared against the thresholds.
- alarmValue—The value of the variable during the last sampling period. This value is compared with the rising and falling thresholds.
- alarmStartupAlarm—The alarm sent when the entry is first activated.
- alarmRisingThreshold—The upper threshold for the sampled variable.
- alarmFallingThreshold—The lower threshold for the sampled variable.
- alarmRisingEventIndex—The eventTable entry used when a rising threshold is crossed.
- alarmFallingEventIndex—The eventTable entry used when a falling threshold is crossed.
- alarmStatus—Method for adding and removing
entries from the table. It can also be used to change the state of
an entry to allow modifications.
Note: If this object is not set to valid, the associated event alarm does not take any action.
jnxRmonAlarmTable
The jnxRmonAlarmTable is a Juniper Networks enterprise-specific extension to alarmTable. It provides additional operational information and includes the following objects:
- jnxRmonAlarmGetFailCnt—The number of times the internal Get request for the variable monitored by this entry has failed.
- jnxRmonAlarmGetFailTime—The value of sysUpTime when an internal Get request for the variable monitored by this entry last failed.
- jnxRmonAlarmGetFailReason—The reason an internal Get request for the variable monitored by this entry last failed.
- jnxRmonAlarmGetOkTime—The value of sysUpTime when an internal Get request for the variable monitored by this entry succeeded and the entry left the getFailure state.
- jnxRmonAlarmState—The current state of this RMON alarm entry.
To view the Juniper Networks enterprise-specific extensions to the RMON Events and Alarms and Event MIB, see https://www.juniper.net/techpubs/en_US/junos10.3/topics/reference/mibs/mib-jnx-rmon.txt.
For more information about the Juniper Networks enterprise-specific extensions to the RMON Events and Alarms MIB, see “RMON Events and Alarms MIB” in the SNMP MIBs and Traps Reference.
