Cisco Systems 15454 16.10.4 History Control RMON Group

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Cisco ONS 15454 Reference Manual, R7.0
78-17191-01
Chapter 16 SNMP
16.10 16.10.4 History Control RMON Group
16.10.3.2 Get Requests and GetNext Requests
Get requests and getNext requests for the etherStatsMulticastPkts and etherStatsBroadcastPkts columns
return a value of zero because the variables are not supported by ONS 15454 Ethernet cards.
16.10.3.3 Row Deletion in etherStatsTable
To delete a row in the etherStatsTable, the SetRequest PDU should contain an etherStatsStatus “invalid”
value (4). The OID marks the row for deletion. If required, a deleted row can be recreated.
16.10.3.4 64-Bit etherStatsHighCapacity Table
The Ethernet statistics group contains 64-bit statistics in the etherStatsHighCapacityTable, which
provides 64-bit RMON support for the HC-RMON-MIB. The etherStatsHighCapacityTable is an
extension of the etherStatsTable that adds 16 new columns for performance monitoring data in 64-bit
format. There is a one-to-one relationship between the etherStatsTable and etherStatsHighCapacityTable
when rows are created or deleted in either table.
16.10.4 History Control RMON Group
The History Control group defines sampling functions for one or more monitor interfaces in the
historyControlTable. The values in this table, as specified in RFC 2819, are derived from the
historyControlTable and etherHistoryTable.
16.10.4.1 History Control Table
The RMON is sampled at one of four possible intervals. Each interval, or period, contains specific
history values (also called buckets). Table 16-9 lists the four sampling periods and corresponding
buckets.
The historyControlTable maximum row size is determined by multiplying the number of ports on a card
by the number of sampling periods. For example, an ONS 15454 E100 card contains 24 ports, which
multiplied by periods allows 96 rows in the table. An E1000 card contains 14 ports, which multiplied by
four periods allows 56 table rows.
16.10.4.2 Row Creation in historyControlTable
The SetRequest PDU must be able to activate a historyControlTable row in one single-set operation. In
order to do this, the PDU must contain all needed values and have a status variable value of 2
(createRequest). All OIDs in the SetRequest PDU should be type OID.0 type for entry creation.
Table 16-9 RMON History Control Periods and History Categories
Sampling Periods
(historyControlValue Variable)
Total Values, or Buckets
(historyControl Variable)
15 minutes 32
24 hours 7
1 minute 60
60 minutes 24