HP StorageWorks 2/16V Brocade Fabric Watch Administrator's Guide - Supporting - Page 33

Configuring events 1 the high threshold (event 1 in Figure 6). When the data value becomes less than the high threshold and buffer value, Fabric Watch triggers a second event (Event 2) to indicate that it has returned to normal operation. The second event will not be triggered until the counter value falls below the high threshold and buffer values. FIGURE 6 Above event trigger with buffer zone Below event trigger The Below event trigger generates an event when a data value becomes less than the low threshold boundary. When a buffer is defined, the event will be triggered when the value goes below the lower threshold. A second event will not be generated until the value crosses the buffer region set above the lower threshold. Changed event trigger Use the Changed event trigger for an element that requires "rate of change" monitoring. When Fabric Watch detects a change in the counter value between two sample periods (defined by the time base), it triggers an event regardless of high or low threshold settings. Figure 7 shows events generated when the data value changes. Each arrow in the figure indicates a generated event. FIGURE 7 Changed threshold Use Changed event triggers with discretion. They are most useful when a change in value is expected to be rare. Monitoring a fabric element that is subject to frequent change generates so many events that it can render it virtually useless. For example, this trigger type is appropriate for FRU failures. It is not appropriate for temperature monitoring. Fabric Watch Administrator's Guide 17 53-0000438-01