BGP route dampening

[Kevin Dorrell]

Can anyone work out what I am doing wrong here. I am sure that it is obvious, but I just cannot see it:

<code>

router bgp 300

no synchronization

bgp router-id 172.16.103.1

bgp log-neighbor-changes

bgp dampening route-map BGP-damped

network 172.16.13.0 mask 255.255.255.0

network 172.16.31.0 mask 255.255.255.0

neighbor 172.16.31.1 remote-as 100

neighbor 172.16.31.1 transport connection-mode active

neighbor 172.16.31.1 update-source FastEthernet0/0.10

neighbor 172.16.36.6 remote-as 600

neighbor 172.16.102.1 remote-as 300

neighbor 172.16.102.1 update-source Loopback103

neighbor 172.16.105.1 remote-as 300

neighbor 172.16.105.1 update-source Loopback103

no auto-summary

:

ip prefix-list BGP-damped seq 5 permit 172.16.21.0/24

ip prefix-list BGP-damped seq 10 permit 172.16.22.0/24

:

route-map BGP-damped permit 10

match ip address prefix-list BGP-damped

R3#show ip bgp dampening

% dampening reconfiguration in progress for IPv4 Unicast

Jan 5 23:49:54.144: %BGP-3-BADROUTEMAP: Bad parameters in the route-map BGP-damped applied for Dampening

</code>

Kevin Dorrell

Luxembourg

[bmcginn · Accepted solution]

Hi Kevin,

Mate, I think you may have to set the dampening parameters in the route-map.. I may well be wrong but thats all I can think of...

try this:

route-map BGP-damped permit 10

match ip address prefix-list BGP-damped

set dampening 15 750 2000 60

exit

where 15 is the half-life decay time

and 750 is the re-use time of the dampened route

and 2000 is the value when the route starts dampening

and 60 is the max time (in mins) to suppress the route...

You probably know that.. buts its friday arvo and i'm procrastinating..

Hope that answers your question...

Brad McGinn

Australia

[Kevin Dorrell]

Absolutely right, all three of you, and all within 10 minutes of each other! I put in the "set deampening", and it all started working. Thanks.

So, to my surprise, this is one use of a route-map where it will not take the default values. I guess you use the route-map version of dampening when you want to dampen selectively, and maybe with different parameters on each prefix.

Thanks again

Kevin Dorrell

Luxembourg

[Danilo Dy · Accepted solution]

Hi Kevin,

Let me try...

I think because the route-map is "permit" which means those prefix-list will be included in the dampening, but there is no set parameters for it. For deny, it's okay without set parameters.

i.e.

route-map BGP-damped permit 10

match ip address prefix-list BGP-damped

set dampening [half-life] [penalty-reusing] [penalty-suppresing] [duration]

Regards,

Dandy

[dongdongliu · Accepted solution]

Hi,kevin

prompt:

% Bad parameters in the route-map BGP-damped applied for Dampening

because of there is no dampening parameters in the route-map BGP-damped

set some parameters like half-life , penalty to start reusing a route , penalty to start suppressing a route , Maximum duration to suppress a stable route