Configuring Bgp Route Dampening - H3C S5600 Series Operation Manual

Operation Manual – Routing Protocol
H3C S5600 Series Ethernet Switches
Disable BGP-IGP route
synchronization
Caution:
BGP-IGP route synchronization is not supported on the switches.

5.4.8 Configuring BGP Route Dampening

Route dampening is used to solve the problem of route instability. Route instability
mainly refers to route flapping. A route flaps if it appears and disappears repeatedly in
the routing table. Route flapping increases the number of BGP update packets,
consumes the bandwidth and CPU time, and even decreases network performance.
Assessing the stability of a route is based on the behavior of the route in the previous
time. Once a route flaps, it receives a certain penalty value. When the penalty value
reaches the suppression threshold, this route is suppressed. The penalty value
decreases with time. When the penalty value of a suppressed route decreases to the
reuse threshold, the route gets valid and is thus advertised again.
BGP dampening suppresses unstable routing information. Suppressed routes are
neither added to the routing table nor advertised to other BGP peers.
Follow these steps to configure BGP route dampening:
To do...
Enter system view
Enter BGP view
Configure BGP
route
dampening-related
parameters
To do...
undo synchronization
Use the command...
system-view
bgp as-number
dampening
[ half-life-reachable
half-life-unreachable
reuse suppress ceiling ]
[ route-policy
route-policy-name ]
Use the command...
—
—
Optional
Not configured by default.
The defaults are as follows:
5-25
Chapter 5 BGP Configuration
Remarks
Required
By default, BGP routes
and IGP routes are not
synchronized.
Remarks
half-life-reachable:
minutes)
half-life-unreachable:
minutes)
reuse: 750
suppress: 2000
ceiling: 16000
15 (in
15 (in