linkdampen

Configures link dampening monitoring and alarms for an interface.
Syntax
linkdampen interval interval_value ethernet unit/slot/port
no linkdampen interval interval_value ethernet unit/slot/port
Command Default

By default, link dampening monitoring and alarms are not enabled.

Parameters
interval interval_value
Defines the sampling period for link flaps and related state changes on the interface. The sampling period is measured in 250 millisecond increments. The interval_value can be configured as a value from 1 through 4, where 4 is equal to 4 X 250 ms, or 1 second.
ethernet unit/slot/port
Interface for which link dampening alarms are to be sent.
Modes

Interface configuration mode

Usage Guidelines

Link dampening may cause momentary traffic loss, convergence issues, and other side effects and should be used only when required.

Link dampening can be applied to any port, including stacking and data ports.

When the linkdampen command is applied to any port in a LAG interface, the configuration is applied to all ports on the LAG.

The recommended sampling interval is 1 second (that is, an interval value of 4).

The linkdampen command can coexist with link-error-disable configuration on the same port.

The no form of the command disables link dampening. Sampling ends on the interface, and alarms are no longer sent.

Examples

The following example configures port 1/1/1 to be monitored for link flaps and for alarms to be sent every 250 milliseconds. Alarms are sent to the user or administrator through syslog and show interfaces ethernet unit/slot/port command output.

device# configure terminal
device(config)# linkdampen interval 1 ethernet 1/1/1
***CAUTION Link-Dampening may cause momentary traffic loss,
may cause status convergence issues and other side effects.
Use Link-Dampening only when required.
Recommended usage Link-Dampening interval 4 - 1 second.

device(config)# show interfaces ethernet 1/1/1
GigabitEthernet1/1/1 is up, line protocol is up 
  Port up for 8 minute(s) 40 second(s) 
  Hardware is GigabitEthernet, address is 609c.9ffe.03cc (bia 609c.9ffe.03cc)
  Configured speed auto, actual 1Gbit, configured duplex fdx, actual fdx
  Configured mdi mode AUTO, actual MDIX
  Member of L2 VLAN ID 1, port is untagged, port state is FORWARDING
  BPDU guard is Disabled, ROOT protect is Disabled, Designated protect is Disabled
  Link Error Dampening is Disabled
  STP configured to ON, priority is level0, mac-learning is enabled
  Openflow is Disabled, Openflow Hybrid mode is Disabled,  Flow Control is config enabled, oper enabled, negotiation disabled
  Mirror disabled, Monitor disabled
  Mac-notification is disabled
  Link Micro Flap Dampening is enabled   <--- Link dampening enabled on Ethernet port 1/1/1
  Damping Interval:250 msecs  Total Microflaps:0  <--- No microflaps during sampling period
  Not member of any active trunks
  Not member of any configured trunks
  No port name
  IPG MII 0 bits-time, IPG GMII 0 bits-time
  MTU 1500 bytes, encapsulation ethernet
  MMU Mode is Store-and-forward
  300 second input rate: 967999344 bits/sec, 202341 packets/sec, 99.85% utilization
  300 second output rate: 967999352 bits/sec, 202341 packets/sec, 99.85% utilization
  105261644 packets input, 62946463112 bytes, 0 no buffer
  Received 105261643 broadcasts, 0 multicasts, 0 unicasts         
  0 input errors, 0 CRC, 0 frame, 0 ignored                       
  0 runts, 0 giants                                               
  105261789 packets output, 62946549822 bytes, 0 underruns
  Transmitted 105261788 broadcasts, 0 multicasts, 0 unicasts
  0 output errors, 0 collisions
  Relay Agent Information option: Disabled
  Protected: No
  MAC Port Security: Disabled

 This port is not being monitored for queue drops 
Egress queues:
Queue counters	  Queued packets	Dropped Packets
         0           105267070             1168968
         1                   0                   0
         2                   0                   0
         3                   0                   0
         4                   0                   0
         5                  23                   0
         6                   0                   0
         7                   0                   0
History
Release version Command history
08.0.70c This command was introduced for ICX 7150 devices.
08.0.90 This command was introduced for all ICX devices (brought forward from patch 08.0.70c).