This command configures the maximum number of prefixes that BGP will accept from a specified neighbor. The prefix limit is compared against the number of prefixes received from the neighbor, including prefixes that are rejected by inbound policy. If the peering session is shut down, the adjacency stays down until the clear ip bgp command is issued for the neighbor. The neighbor can also be brought back up using the neighbor shutdown command followed by the command no neighbor shutdown.
| Default | By default the prefix limit is set to the maximum number of routes that can be installed in the forwarding table. The default warning threshold is 75%. A neighbor that exceeds the limit is shutdown unless the warning-only option is configured. |
| Format | neighbor ip-address maximum-prefix { maximum | unlimited } [threshold] [warning-only] |
| Mode | BGP Router Config |
| Parameter | Description |
|---|---|
| ip-address | The neighbor's IPv4 address. |
| maximum | The maximum number of prefixes BGP will accept from this neighbor. Range is 0 to the maximum number of routes the router supports. |
| unlimited | Do not enforce any prefix limit. |
| threshold | (Optional) When the number of prefixes received from the neighbor exceeds this percentage of the maximum, BGP writes a log message. The range is 1 to 100 percent. The default is 75%. |
| warning-only | (Optional) If BGP receives more than the maximum number of prefixes, BGP accepts the excess prefixes and writes a log message rather than shutting down the adjacency. |
