| Reference for the OPTera Metro 1000 Series Ethernet Service Modules Management Software Operations |
Use the RMON History dialog box to view RMON history statistics for the OM 1000 ESM module.
To open the RMON History dialog box:
Ë From the History tab of the RmonControl dialog box, select an entry and click Graph.
The following table describes the parts of the RMON History dialog box.
SampleIndex
An index that uniquely identifies the particular sample this entry represents among all samples associated with the same historyControlEntry. This index starts at 1 and increases by one as each new sample is taken.
Utilization
The best estimate of the mean physical layer network utilization on this interface during this sampling interval, in hundredths of a percent.
Octets
The total number of octets of data (including those in bad packets) received on the network (excluding framing bits but including FCS octets).
Pkts
The number of packets (including bad packets) received during this sampling interval.
BroadcastPkts
The number of good packets received during this sampling interval that were directed to the broadcast address.
MulticastPkts
The number of good packets received during this sampling interval that were directed to a multicast address. Note that this number does not include packets addressed to the broadcast address.
DropEvents
The total number of events in which packets were dropped by the probe due to lack of resources during this sampling interval. Note that this number is not necessarily the number of packets dropped, it is just the number of times this condition has been detected.
CRCAlignErrors
The number of packets received during this sampling interval that had a length (excluding framing bits but including FCS octets) between 64 and 1518 octets, inclusive, but had either a bad Frame Check Sequence (FCS) with an integral number of octets (FCS Error) or a bad FCS with a non-integral number of octets (Alignment Error)
UndersizePkts
The number of packets received during this sampling interval that were less than 64 octets long (excluding framing bits but including FCS octets) and were otherwise well formed.
OversizePkts
The number of packets received during this sampling interval that were longer than 1518 octets (excluding framing bits but including FCS octets) but were otherwise well formed.
Fragments
The total number of packets received during this sampling interval that were less than 64 octets in length (excluding framing bits but including FCS octets) had either a bad Frame Check Sequence (FCS) with an integral number of octets (FCS Error) or a bad FCS with a non-integral number of octets (Alignment Error).
Note that it is entirely normal for etherHistoryFragments to increment. This is because it counts both runts (which are normal occurrences due to collisions) and noise hits.
Collisions
The best estimate of the total number of collisions on this Ethernet segment during this sampling interval.
The value returned will depend on the location of the RMON probe. Section 8.2.1.3 (10BASE-5) and section 10.3.1.3 (10BASE-2) of IEEE standard 802.3 states that a station must detect a collision, in the receive mode, if three or more stations are transmitting simultaneously. A repeater port must detect a collision when two or more stations are transmitting simultaneously. Thus a probe placed on a repeater port could record more collisions than a probe connected to a station on the same segment would.
Probe location plays a much smaller role when considering 10BASE-T. 14.2.1.4 (10BASE-T) of IEEE standard 802.3 defines a collision as the simultaneous presence of signals on the DO and RD circuits (transmitting and receiving at the same time). A 10BASE-T station can only detect collisions when it is transmitting. Thus probes
placed on a station and a repeater, should report the same number of collisions.
Note also that an RMON probe inside a repeater should ideally report collisions between the repeater and one or more other hosts (transmit collisions as defined by IEEE 802.3k) plus receiver collisions observed on any coax segments to which the repeater is connected.
Line Chart
Graphs the data in the selected cells as a line chart.
Area Chart
Graphs the data in the selected cells as an area chart.
Bar Chart
Graphs the data in the selected cells as a bar chart.
Pie Chart
Graphs the data in the selected cells as a pie chart.
Export Data
Saves a table of data as a tab-delimited text file.
Print Table
Prints a table of data.
Clear counter
Clears the counters.
Close
Closes the Graph Chassis dialog box.
Help
Opens online Help for the Rmon History dialog box.
See also
| Managing RMOM alarms and events |