3Com 3C15500 - Network Director - PC, User Manual, Page: 287 / 924

Components 283
The length of time for which the history is maintained may be configured
via the
Tools > Options dialog box. See “Configuring the Storage of
Monitoring Data” on page 306 for more information.
Each monitor has a menu that can be launched by right-clicking on the
monitor’s live graph.
Some items in the menu are not always
applicable.When this is the case, the menu option is grayed out.
The operations provided by the right-click menu are equivalent to their
corresponding main menu items. See
“Live Graphs Menu” on page 285
for more information.
Displaying Thresholds
Each monitor has a configurable threshold associated with it that
represents an abnormal, or high, state for that monitor.For multi-state
monitors, 3Com Network Director also automatically determines an
appropriate warning threshold for the monitor.These thresholds are used
mainly for event generation: if a monitor stays in the warning or high
state long enough then it will generate an appropriate event.
When a graph for a multi-state monitor includes values that are near or
exceed the warning threshold a yellow horizontal dashed line is displayed
on the graph to indicate the warning threshold level. Additionally, if the
graph includes values that are near or exceed the high threshold a red
horizontal dashed line is displayed on the graph to indicate the high
threshold level.
It is possible to force the Live Graphs window to always show the
thresholds for each multi-state monitor displayed in the live graphs
display area by enabling the
View > Display thresholds option.This option
is enabled by default.
If a graph does not include values that are near or exceed either of the
thresholds, enabling this option allows you to see how close a monitor is
to its threshold values while disabling the option allows you to view more
detail on the monitor’s trends.
The difference between the two can be seen in the two graphs of the
same monitor that are shown below: