Interfaces | 501Link Debounce TimerLink Debounce Timer is supported on platform eThe Link Debounce Timer feature isolates upper layer protocols on Ethernet switches and routers fromvery short-term, possibly repetitive interface flaps often caused by network jitter on the DWDM equipmentconnecting the switch and other devices on a SONET ring. The Link Debounce Timer delays link changenotifications, thus decreasing traffic loss due to network configuration. All interfaces have a built-in timerto manage traffic. This feature extends the time allowed by the upper layers.The SONET ring has its own restore time whenever there is a failure. During this time, however, theEthernet interface connected to the switch will flap. Link Debounce Timer instructs the Ethernet switch todelay the notification of the link change to the upper layers. If the link state changes again within thisperiod, no notification goes to the upper layers, so that the switch remains unaware of the change.Important Points to Remember about Link Debounce Timer• Link Debounce Timer is configurable on physical ports only.• Only 1G fiber, 10/100/1000 copper, 10G fiber, 10G copper are supported.• This feature is not supported on management interfaces or SONET interfaces.• Link Debounce takes effect only when the operational state of the port is up.• Link Debounce is supported on interfaces that also have link dampening configured.• Unlike link dampening, link debounce timer does not notify other protocols.• Changes made do not affect any ongoing debounces. The timer changes take affect from the nextdebounce onward.Assign a debounce time to an interfaceFTOS(conf)#int gi 3/1FTOS(conf-if-gi-3/1)#link debounce time 150FTOS(conf-if-gi-3/1)#=Note: Enabling the link debounce timer causes link up and link down detections to be delayed, resulting intraffic being blackholed during the debouncing period. This situation might affect the convergence andreconvergence of some Layer 2 and Layer 3 protocols.Command Syntax Command Mode Purposelink debounce time [milliseconds] INTERFACE Enter the time to delay link status change notification on thisinterface.Range: 100-5000 ms• Default for Copper is 3100 ms• Default for Fiber is 100 ms
