84
crosses the rising threshold multiple times before it crosses the falling threshold, only the first
crossing triggers a rising alarm event.
Sample types for the alarm group and the private alarm group
The RMON agent supports the following sample types:
• absolute—RMON compares the value of the monitored variable with the rising and falling
thresholds at the end of the sampling interval.
• delta—RMON subtracts the value of the monitored variable at the previous sample from the
current value, and then compares the difference with the rising and falling thresholds.
Protocols and standards
• RFC 4502, Remote Network Monitoring Management Information Base Version 2
• RFC 2819, Remote Network Monitoring Management Information Base Status of this Memo
Configuring the RMON statistics function
RMON implements the statistics function through the Ethernet statistics group and the history group.
The statistics function is available only for Layer 2 and Layer 3 Ethernet interfaces.
The Ethernet statistics group provides the cumulative statistic for a variable from the time the
statistics entry is created to the current time. For more information about the configuration, see
"Creating an RMON Ethernet statistics entry."
The history group provides statistics that are sampled for a variable for each sampling interval. The
history group uses the history control table to control sampling, and it stores samples in the history
table. For more information about the configuration, see "Creating an RMON history control entry."
Creating an RMON Ethernet statistics entry
1. Enter system view.
N/A
2.
interface view.
interface
interface-type
interface-number
N/A
3. Create an entry for
the interface
table.
rmon statistics
entry-number
[
owner
text ]
By default, the
does not contain entries.
You can create one statistics entry for
each Ethernet interface, and up to 100
statistics entries on the device. After the
entry limit is reached, you cannot add
new entries.
Creating an RMON history control entry
You can configure multiple history control entries for one interface, but you must make sure their
entry numbers and sampling intervals are different.
You can create a history control entry successfully even if the specified bucket size exceeds the
available history table size. RMON will set the bucket size as closely to the expected bucket size as
possible.