Link Dampening; Important Points To Remember; Enabling Link Dampening - Dell S6100 Configuration Manual

• module module-number: enter the keyword module then the module number to specify the optional module in which the port is
present.
• number: enter the port number of the 100G port to be split. The range is from 1 to 8.
• Split a 100G port into four 10G ports.
CONFIGURATION Mode
stack-unit stack-unit-number module module-number port number portmode quad speed 10G
• stack-unit-number: enter the stack member unit identifier of the stack member to reset.
• module module-number: enter the keyword module then the module number to specify the optional module in which the port is
present.
• number: enter the port number of the 100G port to be split. The range is from 1 to 8.

Link Dampening

Interface state changes occur when interfaces are administratively brought up or down or if an interface state changes.
Every time an interface changes a state or flaps, routing protocols are notified of the status of the routes that are affected by the change in
state. These protocols go through the momentous task of re-converging. Flapping; therefore, puts the status of entire network at risk of
transient loops and black holes.
Link dampening minimizes the risk created by flapping by imposing a penalty for each interface flap and decaying the penalty exponentially.
After the penalty exceeds a certain threshold, the interface is put in an Error-Disabled state and for all practical purposes of routing, the
interface is deemed to be "down." After the interface becomes stable and the penalty decays below a certain threshold, the interface
comes up again and the routing protocols re-converge.
Link dampening:
• reduces processing on the CPUs by reducing excessive interface flapping.
• improves network stability by penalizing misbehaving interfaces and redirecting traffic.
• improves convergence times and stability throughout the network by isolating failures so that disturbances are not propagated.

Important Points to Remember

• Link dampening is not supported on VLAN interfaces.
• Link dampening is disabled when the interface is configured for port monitoring.
• You can apply link dampening to Layer 2 and Layer 3 interfaces.
• You can configure link dampening on individual interfaces in a LAG.

Enabling Link Dampening

To enable link dampening, use the following command.
• Enable link dampening.
INTERFACE mode
dampening
Examples of the show interfaces dampening Commands
To view the link dampening configuration on an interface, use the show config command.
R1(conf-if-te-1/1/1/1/1)#show config
!
interface TenGigabitEthernet 1/1/1/1
ip address 10.10.19.1/24
398 Interfaces