Dell Force10 S4810P Configuration Manual page 232

When dampening is applied to a route, its path is described by one of the following terms:
• history entry—an entry that stores information on a downed route
• dampened path—a path that is no longer advertised
• penalized path—a path that is assigned a penalty
The CLI example below shows configuring values to start reusing or restarting a route, as well as their
default values.
Figure 9-31. Setting Reuse and Restart Route Values
FTOS(conf-router_bgp)#bgp dampening ?
<1-45>
route-map
<cr>
FTOS(conf-router_bgp)#bgp dampening 2 ?
<1-20000>
FTOS(conf-router_bgp)#bgp dampening 2 2000 ?
<1-20000>
FTOS(conf-router_bgp)#bgp dampening 2 2000 3000 ?
<1-255>
FTOS(conf-router_bgp)#bgp dampening 2 2000 3000 10 ?
route-map
<cr>
Use the following command in the CONFIGURATION ROUTER BGP mode to configure route flap
dampening parameters.
Command Syntax
bgp dampening
[half-life | reuse |
suppress
max-suppress-time]
[ route-map
map-name]
232
| Border Gateway Protocol
Half-life time for the penalty (default = 15)
Route-map to specify criteria for dampening
Value to start reusing a route (default = 750)
Value to start suppressing a route (default = 2000)
Maximum duration to suppress a stable route (default = 60)
Route-map to specify criteria for dampening
Command Mode
CONFIG-ROUTER-BGP
Set readvertise value
Purpose
Enable route dampening.
Enter the following optional parameters to configure route
dampening parameters:
• half-life range: 1 to 45. Number of minutes after which the
Penalty is decreased. After the router assigns a Penalty of 1024
to a route, the Penalty is decreased by half after the half-life
(
period expires. Default: 15 minutes)
• reuse range: 1 to 20000. This number is compared to the
flapping route's Penalty value. If the Penalty value is less than
the reuse value, the flapping route is once again advertised (or no
longer suppressed). Withdrawn routes are removed from history
state. (Default: 750)
• suppress range: 1 to 20000. This number is compared to the
flapping route's Penalty value. If the Penalty value is greater than
the suppress value, the flapping route is no longer advertised
(that is, it is suppressed). (Default: 2000.)
• max-suppress-time range: 1 to 255. The maximum number of
minutes a route can be suppressed. The default is four times the
half-life value. (Default: 60 minutes.)
• route-map map-name: name of a configured route map. Only
match commands in the configured route map are supported. Use
this parameter to apply route dampening to selective routes.
Set time before
value decrements
Set suppress value
Set time to suppress a route