Limiting routes received from a peer or peer group

This feature can prevent attacks that send a large number of BGP routes to the router.

If the number of routes received from a peer or peer group exceeds the upper limit, the router takes one of the following actions based on your configuration:

You can specify a percentage threshold for the router to generate a log message. When the ratio of the number of received routes to the maximum number reaches the percentage value, the router generates a log message.

To limit routes that a router can receive from a peer or peer group (IPv4 unicast/multicast address family):

Step

Command

Remarks

1. Enter system view.

system-view

N/A

2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view.

  • Enter BGP IPv4 unicast address family view:

    1. bgp as-number [ instance instance-name ]

    2. address-family ipv4 [ unicast ]

  • Enter BGP-VPN IPv4 unicast address family view:

    1. bgp as-number [ instance instance-name ]

    2. ip vpn-instance vpn-instance-name

    3. address-family ipv4 [ unicast ]

  • Enter BGP IPv4 multicast address family view:

    1. bgp as-number [ instance instance-name ]

    2. address-family ipv4 multicast

N/A

3. Specify the maximum number of routes that a router can receive from a peer or peer group.

peer { group-name | ipv4-address [ mask-length ] } route-limit prefix-number [ { alert-only | discard | reconnect reconnect-time } | percentage-value ] *

By default, the number of routes that a router can receive from a peer or peer group is not limited.

To limit routes that a router can receive from a peer or peer group (IPv6 unicast/multicast address family):

Step

Command

Remarks

1. Enter system view.

system-view

N/A

2. Enter BGP IPv6 unicast address family view, BGP-VPN IPv6 unicast address family view, or BGP IPv6 multicast address family view.

  • Enter BGP IPv6 unicast address family view:

    1. bgp as-number [ instance instance-name ]

    2. address-family ipv6 [ unicast ]

  • Enter BGP-VPN IPv6 unicast address family view:

    1. bgp as-number [ instance instance-name ]

    2. ip vpn-instance vpn-instance-name

    3. address-family ipv6 [ unicast ]

  • Enter BGP IPv6 multicast address family view:

    1. bgp as-number [ instance instance-name ]

    2. address-family ipv6 multicast

N/A

3. Specify the maximum number of routes that a router can receive from a peer or peer group.

peer { group-name | ipv6-address [ prefix-length ] } route-limit prefix-number [ { alert-only | discard | reconnect reconnect-time } | percentage-value ] *

By default, the number of routes that a router can receive from a peer or peer group is not limited.