Datasheet

16-20
Cisco ONS 15454 SDH Reference Manual, R7.0
October 2008
Chapter 16 SNMP
16.10.5 Ethernet History RMON Group
To create a creation SetRequest PDU for the historyControlTable, the following values are required:
• The historyControlDataSource and its desired value
• The historyControlBucketsRequested and it desired value
• The historyControlInterval and its desired value
• The historyControlOwner and its desired value
• The historyControlStatus with a value of createRequest (2)
The historyControlBucketsRequested OID value is ignored because the number of buckets allowed for
each sampling period, based upon the historyControlInterval value, is already fixed as listed in
Table 16-9.
The historyControlInterval value cannot be changed from the four allowed choices. If you use another
value, the SNMP agent selects the closest smaller time period from the set buckets. For example, if the
set request specifies a 25-minute interval, this falls between the 15-minute (32 bucket) variable and the
60-minute (24 bucket) variable. The SNMP agent automatically selects the lower, closer value, which is
15 minutes, so it allows 32 buckets.
If the SetRequest PDU is valid, a historyControlTable row is created. If the row already exists, or if the
SetRequest PDU values do not make sense or are insufficient, the SNMP agent does not create the row
and returns an error code.
16.10.4.3 Get Requests and GetNext Requests
These PDUs are not restricted.
16.10.4.4 Row Deletion in historyControl Table
To delete a row from the table, the SetRequest PDU should contain a historyControlStatus value of 4
(invalid). A deleted row can be recreated.
16.10.5 Ethernet History RMON Group
The ONS 15454 SDH implements the etherHistoryTable as defined in RFC 2819. The group is created
within the bounds of the historyControlTable and does not deviate from the RFC in its design.
64-bit Ethernet history for the HC-RMON-MIB is implemented in the etherHistoryHighCapacityTable,
which is an extension of the etherHistoryTable. The etherHistoryHighCapacityTable adds four columns
for 64-bit performance monitoring data. These two tables have a one-to-one relationship. Adding or
deleting a row in one table will effect the same change in the other.
16.10.6 Alarm RMON Group
The Alarm group consists of the alarmTable, which periodically compares sampled values with
configured thresholds and raises an event if a threshold is crossed. This group requires the
implementation of the event group, which follows this section.
16.10.6.1 Alarm Table
The NMS uses the alarmTable to determine and provision network performance alarmable thresholds.