Alcatel-Lucent 6850-48 Reference Guide
BGP Commands
page 44-28
OmniSwitch CLI Reference Guide
September 2009
• The half-life value configures the half-life duration for a reachable route. After the time interval speci-
fied in this command, the penalty value for the route will be reduced by half. This command sets the
duration in seconds during which the accumulated stability value is reduced by half if the route is
considered reachable, whether suppressed or not. A larger value may be desirable for routes that are
known for their instability. A larger value will also result in a longer suppression time if the route
exceeds the flapping rate.
duration in seconds during which the accumulated stability value is reduced by half if the route is
considered reachable, whether suppressed or not. A larger value may be desirable for routes that are
known for their instability. A larger value will also result in a longer suppression time if the route
exceeds the flapping rate.
• The reuse value configures the number of route withdrawals necessary to begin readvertising a previ-
ously suppressed route. If the penalty value for a suppressed route fall below this value, then it will be
advertised again. This command sets the reuse value, expressed as a number of route withdrawals.
When the stability value for a route reaches or falls below this value, a previously suppressed route will
be advertised again. The instability metric for a route is decreased by becoming more stable and by
passing half-life time intervals
advertised again. This command sets the reuse value, expressed as a number of route withdrawals.
When the stability value for a route reaches or falls below this value, a previously suppressed route will
be advertised again. The instability metric for a route is decreased by becoming more stable and by
passing half-life time intervals
• The suppress value configures the cutoff value, or number of route withdrawals, at which a flapping
route is suppressed and no longer advertised to BGP peers. This value is expressed as a number of
route withdrawals. When the stability value for a route exceeds this cutoff value, the route advertise-
ment is suppressed.
route withdrawals. When the stability value for a route exceeds this cutoff value, the route advertise-
ment is suppressed.
• The max-suppress-time value configures the maximum time (in seconds) a route can be suppressed.
This time is also known as the maximum holdtime or the maximum instability value. Once this time is
reached the route flap history for a route will be deleted and the route will be advertised again (assum-
ing it is still reachable). This maximum holdtime as applied on an individual route basis. Each
suppressed route will be held for the amount of time specified in this command unless the route is re-
advertised by falling below the reuse value.
reached the route flap history for a route will be deleted and the route will be advertised again (assum-
ing it is still reachable). This maximum holdtime as applied on an individual route basis. Each
suppressed route will be held for the amount of time specified in this command unless the route is re-
advertised by falling below the reuse value.
• Entering the command with no variables returns the variables back to their defaults.
Examples
-> ip bgp dampening
-> ip bgp dampening half-life 20 reuse 800 suppress 60 max-suppress-time 40
-> no ip bgp dampening
Release History
Release 6.1; command was introduced.
Related Commands
Clears the dampening history data for all routes on the router, reset-
ting route flap counters and unsuppressing any routes that had been
suppressed due to route flapping violations.
ting route flap counters and unsuppressing any routes that had been
suppressed due to route flapping violations.
Displays the BGP route dampening settings.
Displays BGP dampening statistics.