Configures the route flap dampening feature for a BGP neighbor.
| all | Specifies that the configuration applies to all neighbors in the specified address family. If no address family is specified or if an IPv4 address is specified, the configuration applies to all IPv4 neighbors. If an IPv6 address family is specified, the configuration applies to all IPv6 neighbors. |
| remoteaddr | Specifies the IPv4 or IPv6 address of a BGP neighbor. The switch uses the IP address format to determine if the address is an IPv4 or IPv6 address. |
| ipv4-unicast | Specifies the IPv4 unicast address family. |
| ipv4-multicast | Specifies an IPv4 multicast address family. |
| ipv6-unicast | Specifies the IPv6 unicast address family. |
| ipv6-multicast | Specifies an IPv6 multicast address family. |
| vpnv4 | Specifies the VPNv4 address family for Layer 3 VPN support. This address family is applicable for PE to PE BGP neighbor sessions only. Using this keyword may prompt warning or error messages if executed for a regular BGP neighbor session, or for a PE to CE neighbor session. |
| half-life | Specifies the dampening half life. Range is 1 to 45 minutes. |
| reuse-limit | Specifies the reuse limit. Range is 1 to 20000. |
| suppress-limit | Specifies the suppress limit. Range is 1 to 20000. |
| max-suppress | Specifies the maximum hold down time. Range is 1 to 255 minutes. |
| policy-filter | Specifies a policy. |
This feature is disabled by default.
If no address family is specified and an IPv4 address is detected, IPv4 unicast is the default address family.
This command applies to the current VR or VRF context.
If you do not specify an address family, this command applies to the IPv4 unicast address family. To apply this command to an address family other than the IPv4 unicast address family, you must specify the address family.
Note
For an IPv6 peer, an IPv6 address family must be specified, because an IPv6 peer does not support IPv4 address families. If no address family is specified for an IPv6 peer, the default, the IPv4 unicast address family, applies and the command fails. Similarly an IPv4 peer only supports IPv4 address families and the command fails if an IPv6 address family is specified.
The half life is the period of time, in minutes, during which the accumulated penalty of a route is reduced by half. The range is 1 to 45 minutes, and the default is 15 minutes.
The reuse limit is the penalty value below which a route is used again. The range is 1-20,000, and the default is 750.
The suppress limit is the penalty value above which a route is suppressed. The range is 1-20,000, and the default is 2,000.
The maximum hold down time is the maximum time a route can be suppressed, no matter how unstable it has been, as long as it no longer flaps. The range is 1-255 minutes, and the default is 4 * the half life.
If you change dampening parameters when routes are in suppressed or history state, the new dampening parameters apply only to routes in the active state. Routes in the suppressed or history state continue to use the old dampening parameters until they become active, at which time they use the updated dampening parameters.
Instead of explicitly configuring the dampening parameters using the command line, you can associate a policy using the policy-filter option. Multiple sets of parameters can be supplied using a policy.
Use the following command to disable route flap dampening for BGP neighbors:
configure bgp neighbor [remoteaddr | all] {address-family [ipv4-unicast | ipv4-multicast | ipv6-unicast | ipv6-multicast | vpnv4]} no-dampeningTo configure this feature on Layer 3 VPNs, you must configure this feature in the context of the MPLS-enabled VR; this feature is not supported for BGP neighbors on the CE (VRF) side of the PE router.
The following command configures route flap dampening to the BGP neighbor at 192.168.1.22 to the default values:
configure bgp neighbor 192.168.1.22 dampening
This command was first available in ExtremeXOS 10.1.
This command required a specific license in ExtremeXOS 11.1.
Support for IPv6 was added in ExtremeXOS 12.6 BGP.
Support for Layer 3 VPNs was added in ExtremeXOS 15.3.
This command is available on platforms that support the appropriate license. For complete information about software licensing, including how to obtain and upgrade your license and which licenses support the BGP feature, see the Feature License Requirements document.
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