Specifies the maximum number of IP network prefixes (routes) that can be learned from a specified neighbor or peer group.
This feature is disabled.
BGP address-family IPv4 unicast configuration mode
BGP address-family IPv6 unicast configuration mode
BGP address-family IPv4 unicast VRF configuration mode
BGP address-family IPv6 unicast VRF configuration mode
BGP address-family L2VPN EVPN configuration mode
The no form of the command restores the defaults.
When a neighbor session is torn down due to maximum-prefix value being exceeded, The maximum number of prefixes that can be learned from a specific neighbor or from a peer-group is specified in the maximum-prefix configuration. The teardown parameter for this command indicates that the neighbor session will be brought down when the number of learned prefixes exceeds the value configured in the maximum-prefix configuration.
When a session is brought down due to the above reason, it has to be manually restored using either of the clear ip bgp neighbor all or the clear ip bgp neighbor commands.
The restart-interval parameter of the neighbor maximum-prefix command automatically restarts a session brought down due to maximum-prefix being exceeded. This is only applicable when both the maximum-prefix and teardown parameters are configured. When applied, the neighbor session is automatically restarted after the duration specified in the restart-interval-in-minutes value expires.
The following example sets the maximum number of prefixes that will be accepted from the neighbor with the IP address 10.11.12.13 to 100000, and sets the threshold value to 80%.
device# configure terminal device(config)# router bgp device(config-bgp-router)# address-family ipv4 unicast device(config-bgp-ipv4u)# neighbor 10.11.12.13 maximum-prefix 100000 threshold 80
The following example, for VRF instance "red," sets the maximum number of prefixes that will be accepted from the neighbor with the IPv6 address 2001:2018:8192::125 to 100000, and sets the threshold value to 90%.
device# configure terminal device(config)# router bgp device(config-bgp-router)# address-family ipv6 unicast vrf red device(config-bgp-ipv6u-vrf)# neighbor 2001:2018:8192::125 maximum-prefix 100000 threshold 90
The following example sets the maximum number of prefixes that will be accepted from the neighbor with the IP address 10.1.2.3 to 100000 in L2VPN EVPN configuration mode.
device# configure terminal device(config)# router bgp device(config-bgp-router)# address-family l2vpn evpn device(config-bgp-evpn)# neighbor 10.1.2.3 maximum-prefix 100000
The following example extends the previous example to configure a threshold value to generate a RASLOG entry. The threshold value is set at 80% of the configured prefixes.
device# configure terminal
device(config)# router bgp
device(config-bgp-router)# address-family l2vpn evpn
device(config-bgp-evpn)# neighbor 10.1.2.3 maximum-prefix 100000 80
The following example sets the maximum number of prefixes that will be accepted from the neighbor with the IP address 10.1.2.3 to 100000 in L2VPN EVPN configuration mode. It also configures a threshold for generating a RASLOG entry. The example command then configures a restart interval to restart the session after 7 minutes when the interface is shut down due to maximum prefixes being exceeded.
device# configure terminal
device(config)# router bgp
device(config-bgp-router)# address-family l2vpn evpn
device(config-bgp-evpn)# neighbor 10.1.2.3 maximum-prefix 100000 80 restart-interval 7