Brocade Fabric Watch Administrator's Guide v6.1.0 (53-1000601-02, June 2008)

20 Fabric Watch Administrator’s Guide
53-1000601-02
Port persistence
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DRAFT: BROCADE CONFIDENTIAL
Port persistence
The data collected in port monitoring can vary a great deal over short time periods. Therefore, the
port can become a source of frequent event messages (the data can exceed the threshold range
and return to a value within the threshold range).
Fabric Watch uses port persistence for a port event that requires the transition of the port into a
marginal status. Fabric Watch does not record any event until the event persists for a length of time
equal to the port persistence time. If the port returns to normal boundaries before the port
persistence time elapses, Fabric Watch does not record any event.
The port persistence time is measured in seconds, and can be configured. Configuring the port
persistence time to zero disables this feature. The default value for port persistence is 18 seconds.
Port fencing
A port that is consistently unstable can harm the responsiveness and stability of the entire fabric
and diminish the ability for the management platform to control and monitor the switches within
the fabric. Port Fencing is a Fabric Watch enhancement that takes the Port class, E_Port class, and
F/FL_Port class ports offline if the user-defined thresholds are exceeded.
NOTE
Port Fencing is not enabled by default. The user must manually enable Port Fencing.
When a port that has exceeded its user-defined thresholds is fenced by software, the port is placed
into the disabled state and held offline, thereby removing the port’s capability to transmit or
receive frames. Once a port is disabled, user intervention is necessary for frame traffic to resume
on the port.