# Configuring Alarms

Configuring an alarm involves choosing an event type, rising (set alarm) and falling (clear alarm) thresholds, a sampling frequency, and finally enabling or disabling the alarm.

Excessive Port Errors

The switch monitors a set of port errors and generates alarms based on user-defined sample intervals and thresholds. Port errors include:

* CRC errors

* Decode errors

* ISL connection count

* Login errors

* Logout errors

* Loss-of-signal errors

If the count for any of the port errors exceeds the rising threshold for three consecutive sample intervals, the switch generates an alarm and disables the affected port, changing its operational state to “down”. Port errors can be caused by:

* Thresholds are too low or the sample interval is too small

* Faulty Fibre Channel port cable

* Faulty SFP

* Faulty port

* Fault device or HBA

To configure alarms on a SANbox2 or SANbox2-64 switch, do the following:

1. In the faceplate display, open the Switch menu and select Configure Alarm Thresholds.

2. The Alarm Threshold Configuration dialog prompts you to enable or disable all alarms, select an event, set thresholds, set a sample interval, and enable or disable an individual alarm.

3. Check the Enable All Alarm Thresholds box to enable (disabled is the default - unchecked) monitoring for all the individual alarm types that are enabled. The Enable All Alarm Thresholds box is the master control for the individual alarms. For example, the switch will monitor CRC errors only if both the CRC Error Enable box and the Enable All Alarm Thresholds box are checked.

4. Select an event type from the Alarm Threshold pull-down menu. Choose from the following options:

* CRC Error Monitoring

* Decode Error Monitoring

* ISL Monitoring

* Login Monitoring

* Logout Monitoring

* Loss of Signal Monitoring

5. Enter a value for the falling threshold. The falling threshold is the count below which an event becomes eligible to generate an alarm.

6. Enter values for the rising and falling thresholds. The rising threshold is the count above which an alarm is generated. When the count exceeds the rising threshold, one alarm is generated. The switch will not generate another alarm for that event until the count descends below the falling threshold, resetting the eligibility, and again exceeds the rising threshold. The default sample interval is 30 seconds. An alarm is cleared when the threshold monitoring detects that the error rate has fallen below the falling threshold.

Note: The switch will down a port if a rising threshold alarm is not cleared after three consecutive sample intervals.

7. Enter a sample interval in milliseconds. The sample interval defines the period of time in which to count events.

8. Check the Enable box to make the alarm eligible for use. Repeat steps 3 through 7 for each alarm you want to configure or enable.

8. Check the Enable box to make the alarm eligible for use. Repeat steps 4 through 8 for each alarm you want to configure or enable. You must also check the Enable All Alarm Thresholds box (the default is unchecked), which is the master control for all alarm configurations.

9. Click the OK button to implement all enabled alarms.

Below is a graphical representation of an alarm threshold.