Port Flap Dampening Configuration - Brocade Communications Systems FastIron Administration Manual

The following example shows the message that appears when the port does not have a configured
voice VLAN.
device# show voice-vlan ethernet 2
Voice vlan is not configured for port 2.
To view the voice VLAN for all ports, use the show voice-vlan command. The following example shows
the command output results.
device# show voice-vlan
Port ID
2
8
15
Syntax: show voice-vlan [ ethernet port ]

Port flap dampening configuration

Port Flap Dampening increases the resilience and availability of the network by limiting the number of
port state transitions on an interface.
If the port link state toggles from up to down for a specified number of times within a specified period,
the interface is physically disabled for the specified wait period. Once the wait period expires, the port
link state is re-enabled. However, if the wait period is set to zero (0) seconds, the port link state will
remain disabled until it is manually re-enabled.
Port flap dampening configuration notes
• When a flap dampening port becomes a member of a trunk group, that port, as well as all other
member ports of that trunk group, will inherit the primary port configuration. This means that the
member ports will inherit the primary port flap dampening configuration, regardless of any previous
configuration.
• The Brocade device counts the number of times a port link state toggles from "up to down", and not
from "down to up".
• The sampling time or window (the time during which the specified toggle threshold can occur before
the wait period is activated) is triggered when the first "up to down" transition occurs.
• "Up to down" transitions include UDLD-based toggles, as well as the physical link state.
Configuring port flap dampening on an interface
This feature is configured at the interface level.
device(config)# interface ethernet 2/1
device(config-if-e10000-2/1)# link-error-disable 10 3 10
Syntax: [no] link-error-disable toggle-threshold sampling-time-in-sec wait-time-in-sec
The toggle-threshold is the number of times a port link state goes from up to down and down to up
before the wait period is activated. Enter a value from 1 - 50.
The sampling-time-in-sec is the amount of time during which the specified toggle threshold can occur
before the wait period is activated. The default is 0 seconds. Enter 1 - 65535 seconds.
The wait-time-in-sec is the amount of time the port remains disabled (down) before it becomes enabled.
Enter a value from 0 - 65535 seconds; 0 indicates that the port will stay down until an administrative
override occurs.
FastIron Ethernet Switch Administration Guide
53-1003625-01
Voice-vlan
1001
150
200
Port flap dampening configuration
77