Service Manual

Figure 48. Interface State Change
Consider an interface periodically flaps as shown above. Every time the interface goes down, a penalty (1024) is added. In
the above example, during the first interface flap (flap 1), the penalty is added to 1024. And, the accumulated penalty will
exponentially decay based on the set half-life, which is set as 10 seconds in the above example. During the second interface flap
(flap 2), again the penalty (1024) is accumulated. When the accumulated penalty exceeds the configured suppress threshold
(2400), the interface state is set to Error-Disabled state. After the flap (flap 3), the interface flap stops. Then, the accumulated
penalty decays exponentially and when it reaches below the set reuse threshold (300), the interface is unsuppressed and the
interface state changes to “up” state.
Interfaces
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