Active Alarm Table; Alarm History - 3Com V7122 User Manual

A carrier-grade alarm system is characterized by the following:
The device has a mechanism that allows a manager to determine which alarms are
currently active in the device. That is, the device maintains an active alarm table.
The device has a mechanism to allow a manager to detect lost alarm raise and clear
notifications [sequence number in trap, current sequence number MIB object].
The device has a mechanism to allow a manager to recover lost alarm raise and clear
notifications [maintains a log history].
The device sends a cold start trap to indicate that it is starting. This allows the EMS to
synchronize its view of the device's active alarms.
When the SNMP alarm traps are sent, the carrier-grade alarm system does not add or delete
alarm traps as part of the feature. This system provides the mechanism for viewing of history
and current active alarm information.

Active Alarm Table

The device maintains an active alarm table to allow a manager to determine which alarms
are currently active in the device. Two views of the active alarm table are supported by the
agent:
acActiveAlarmTable in the enterprise acAlarm
alarmActiveTable and alarmActiveVariableTable in the IETF standard ALARM-MIB
(rooted in the AC tree)
The acActiveAlarmTable is a simple, one-row per alarm table that is easy to view with a MIB
browser.
The ALARM-MIB is currently a draft standard and therefore has no OID assigned to it. In the
current software release, the MIB is rooted in the experimental MIB subtree. In a future
release, after the MIB has been ratified and an OID assigned, it is to move to the official OID.

Alarm History

The device maintains a history of alarms that have been raised and traps that have been
cleared to allow a manager to recover any lost, raised or cleared traps. Two views of the
alarm history table are supported by the agent:
acAlarmHistoryTable in the enterprise acAlarm
nlmLogTable and nlmLogVariableTable in the standard NOTIFICATION-LOG-MIB
As with the acActiveAlarmTable, the acAlarmHistoryTable is a simple, one-row-per-alarm
table that is easy to view with a MIB browser.
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