UMN:CLI
User Manual
V8102
610
12.1.14
Route Flap Dampening
The route dampening minimizes the instability caused by route flapping. A penalty is add-
ed for every flap in a flapping route. As soon as the total penalty reaches the
“suppress”
limit the advertisement of the route is suppressed. This penalty is decayed according to
the configured
“half time” value. Once the penalty is lower than the “reuse” limit, the route
advertisement is un-suppressed.
To enable the route-flap dampening, use the following command.
Command
Mode
Description
bgp dampening
Router
AF
Enables the route-flap dampening.
To configure BGP dampening parameters, use the following command.
Command
Mode
Description
bgp dampening
<1-45>
Router
AF
Configures BGP dampening parameters.
1-45: reachability half-life time in minute (default: 15
minutes)
1-20000: reuse limit value (default: 750)
1-20000: suppress limit value (default: 2000)
1-255: max-suppress-time (default: 60 minutes)
1-45: un-reachability half-life time for penalty
bgp
dampening
<1-45>
<1-
20000> <1-255>
bgp
dampening
<1-45>
<1-
20000> <1-20000> <1-255> <1-
45>
bgp
dampening
route-map
WORD
Specifies the route-map criteria for dampening.
WORD: route-map name
When the penalty for a suppressed route decays below the
“reuse value”, the routes be-
come unsuppressed. When the penalty for a route exceeds the
“suppress value”, the
route is suppressed.
The
“reachability half-life time” is for the penalty to decrease to one-half of its current val-
ue. The
“max-suppress-time is the maximum time that a dampened route is suppressed.
This value is 4 times the half-life time.
To delete the configured BGP dampening parameters, use the following command.
Command
Mode
Description
no bgp dampening
<1-45>
Router
AF
Deletes the configured BGP dampening parameters.
no bgp dampening
<1-45> <1-
20000> <1-255>
no bgp dampening
<1-45> <1-
20000> <1-20000> <1-255> <1-
45>
no bgp dampening route-map
[
WORD
]
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