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14.8.3.15 bgp dampening
Command: bgp dampening [<1-45>] [<1-20000> <1-20000> <1-255>] [<1-45>]
no bgp dampening [<1-45>] [<1-20000> <1-20000> <1-255>] [<1-45>]
Function:
Configure the route dampening. The “
no bgp dampening [<1-45>]
[<1-20000> <1-20000> <1-255>] [<1-45>]
” command cancels the route dampening
function
Parameter: <1-45>
:
>
: Respectively the penalty half-lives of accessible and unaccessible
route, namely the penalty value is reduced to half of the previous value, in
minutes.
<1-20000>
: Respectively the penalty reuse border and restrain border
<1-255>
: Maximum restrain route time, in minutes
Default:
Half-life of accessible route is 15 minutes, 5 minutes for unaccessible. The
restrain border is 2000, reuse border is 750, and maximum restrain time is 60 minutes
Command Mode:
BGP routing mode.
Usage Guide:
Abundant route update due to unstable route could be reduced with route
dampening technology, of which the algorithm is lay penalty on the route when the route
fluctuates, and when penalty exceeds the restrain border this route will no longer be
advertised. The penalty value will be reduced by time by the half-life index regulation if
the route keeps stable and finally be advertised again when the penalty falls below the
border or the restrain time exceeds the maximum restrain time. This command is for
enabling/disabling the route dampening and configuring its parameters
Example:
Switch(config-router)# bgp dampening
14.8.3.16 bgp default
Command: bgp default {ipv4-unicast|local-preference <0-4294967295>}
no bgp default {ipv4-unicast|local-preference [<0-4294967295>]}
Function:
Set the BGP defaults, the “
no bgp default {ipv4-unicast|local-preference
[<0-4294967295>]}
” command cancels this configuration
Parameter: <0-4294967295>
: Default local priority
Default:
The IPv4 unicast is default enabled when BGP is enabled. The default priority is
100.
Command Mode:
BGP routing mode.
Usage Guide:
IPv4 unicast address-family is default enabled in BGP. Cancel this setting
with no bgp default ipv4-unicast command so to not enable this address-family in default.
Default local priority can be configured through bgp default local-preference command.
Example:
Configure on 10.1.1.66
Switch(config)#router bgp 200
