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If you selected BGP from the Protocol drop-down list, do the following:

1. In BGPD Enabled, use the toggle switch to enable (True) or disable (False) BGPD.

2. Expand the IPV4 Prefix List section, and configure the listed fields.

When you configure an IPv4 prefix list, you filter BGP routes by assigning the prefix list to a neighbor rather than by using an autonomous system (AS) path filter. The process for evaluating a prefix against a prefix list ends when a match is found. For example, to disallow redistribution of a route for 10.0.0.0/24 through BGP, define an IPv4 prefix list that includes this prefix; the system will reference it from the BGP redistribution routing map.

  • Name: Enter a name for the IPv4 prefix list. Create a name that does not exceed 64 characters in length. Use numbers, any special characters, uppercase and lowercase letters, and even spaces. Start and end a name with any character but not a space. Leading and trailing spaces will be trimmed off automatically.
  • Description: Enter the description for the IPv4 prefix list.
  • Click Add and specify the following to add an IPv4 prefix to the list:
    • ACTION: Choose the action you want to apply to this IPv4 prefix list. Choose either DENY or PERMIT to disallow or allow traffic to the route that matches the prefix list.
    • PREFIX: Enter the IPv4 prefix. For example, to allow or disallow traffic to 10.0.0.0/8, enter 10.0.0.0/8.
    • IPV4 PREFIX LENGTH GE: Specifies the prefix length greater than or equal to the subnet value. This is the lowest value of the range of prefix length.
    • IPV4 PREFIX LENGTH LE: Specifies the prefix length less than or equal to the subnet value. This is the highest value of the range of prefix length.
    • SEQUENCE: To specify the entry point of this IPv4 prefix list among other BGP configurations, enter a number from 1 to 2147483646. 
      For example, if you configure ACTION = Permit, IPv4 PREFIX = 10.0.0.0/8, and IPv4 PREFIX LENGTH LESS OR EQUAL = 19, then all networks that fall within the 10.0.0.0/8 range AND have a subnet mask of /19 or less will be allowed through BGP.
  • To delete a selected IPv4 prefix, click Remove. 

3. Expand the Route Map drop-down section, and configure the fields listed next. 

A route map evaluates the matching conditions until a successful match occurs. After the match occurs, the route map stops evaluating the matching conditions and starts executing the conditions in the order in which they were configured. If a successful match does not occur, the route map “falls through” and evaluates the next sequence number of the route map until all configured route map entries have been evaluated or a successful match has occurred. Each route map sequence is tagged with a sequence number, to identify the entry. Route map entries are evaluated from the lowest sequence number to the highest sequence number. 

  • Name: Enter the name of the route map.
  • In the Route Map section, click Add and specify the following: 
    • Action: Choose either DENY or PERMIT for this route map. 
    • Description: Enter a description for this route map.
    • Sequence: To determine the entry point of this route map, enter a number from 1 to 2147483646.
    • Match Condition: Click Add and specify the following to add a matching condition and a condition value:
      • CONDITION: Enter a name for the matching condition.
      • CONDITION VALUE: Enter a matching value for this condition.
    • To delete a condition, select it and click Remove. 
  • Set Community: Click Add and complete the following to configure community settings for the route map. You can use the community attribute to control the routing policy in the upstream service provider network.
    • COMMUNITY: Enter the community value.
    • DESCRIPTION: Enter a description for this community attribute.
    • To delete a community, select it and click Remove. 
  • Click Add in the bottom-right corner of the section to add the Route Map.

4. Expand the BGPD Config drop-down section, and do the following to set parameters for the BGP configuration file:

  • Expand the Address Family IPv4 Unicast section, and specify the following:
      • Admin Distance: An administrative distance or route preference is a rating of trustworthiness of a source of routing information. An administrative distance is the first criterion that a router uses to determine the routing protocol to be used if two protocols provide the route information for the same destination. An administrative distance has only local significance and is not advertised in routing-related updates.
        • External: Enter the rating for routes learned from EBGP (External Border Gateway Protocol). The smaller the number, the more trustworthy the protocol. EBGP routes received from an EBGP peer can be advertised to EBGP and IBGP peers. 
        • Internal: Enter the rating for routes learned from IBGP (Internal Border Gateway Protocol). The smaller the number, the more trustworthy the protocol. IBGP routes received from an IBGP peer cannot be advertised to another IBGP peer but can be advertised to an EBGP peer. 
        • Local: Enter the local IP address.
      • Aggregate Route: Aggregate specific routes into one route. This will enable you to hide a number of prefixes from being advertised to neighbors.
        • Click Add to add the IP ADDRESSES of the router into which you want other routes to aggregate.
        • To delete an aggregate route, select it and click Remove. 
      • In the Maximum Paths section, configure the fields listed. These settings determine if and when a router will add multiple EBGP or IBGP routes to the IP routing table.
        • EBGP: Enter the number of possible IP routes learned from EBGP.
        • IBGP: Enter the number of possible IP routes learned from IBGP.
      • Network Config: 
        • Click Add to add an IPv4 or IPv6 network config, and then enter the IP ADDRESSES.
        • To delete a network config, select the IP address and click Remove.
  • Expand the Global section, and specify the following:
      • Fast External Failover: If the route used to reach the peer is invalid or goes offline, toggle this to True to terminate external BGP sessions of any directly adjacent peer, without waiting for the hold-down timer to expire. Toggle to False to disable fast external failover.
      • Graceful Restart: Toggle this to True to announce a graceful restart. If you toggle to False, the graceful restart capability is not announced. 
      • Graceful Shutdown: Toggle this to True to announce a graceful shutdown. If you toggle to False, the graceful restart capability is not announced.
      • Local As: Enter the number of the AS here. When you enter the AS number, the system permits a router to appear to be a member of the second AS in addition to being a member of the actual AS.
      • Log Neighbor Changes: Toggle this to True to log changes from a BGP neighbor.
      • Router Id: Enter the router ID, which is a 4-byte field that is set to the highest IP address on the router. It is used in the BGP algorithm to determine the best path to a destination, and the preference is for the BGP router with the lowest router ID. By using the configured hold time and the KEEPALIVE messages, the BGP mechanism ensures the BGP neighbors are still alive. Configure the following global BGP timers:
      • Hold Time: Enter the number of seconds that a router will wait for incoming BGP messages before it assumes the neighbor is dead. This heartbeat mechanism ensures that the BGP neighbors are healthy and alive. The hold time you enter here sets the hold timer for each BGP neighbor. Upon receipt of an UPDATE or a KEEPALIVE message, the hold timer resets to the initial value. If the hold timer reaches zero, the BGP session is terminated, the routing paths from that neighbor are removed, and, for the prefixes affected, an appropriate message about withdrawal of an update route is sent to other BGP neighbors. 
      • Keep Alive: Enter the number of seconds for the time interval during which a router sends KEEPALIVE messages to the BGP neighbors, to keep the BGP session alive. Typically, the keep alive timer is one-third of the hold time.
      • Update Delay: Enter the number of seconds for the minimum delay between updates for a neighbor session.
  • Expand the Neighbors section, and specify the following to set your BGP neighbor configuration. For BGP to run in your network, you must configure at least one peer group that includes at least one neighbor. You first determine which neighbors are internal or external to your local AS.
    • Click Add and specify the following:
      • PEER GROUP NAME: Enter the BGP peer group name.
      • REMOTE ADDRESS: Enter the remote IP address for the BGP peer group.
      • Local Interface: Specify the name of the local interface for your BGP peer group. This is a required field. 
      • Local Port: Specify the local port you want to use for your BGP peer group. This is a required field. 
      • Remote Address: Specify the remote IP address you want to use for your BGP peer group. This is a required field. 
      • Expand the Neighbor Param drop-down section, and specify the following:
        • Description: Enter the description of the BGP peer group.
        • Graceful Restart: Toggle this to True to enable and False to disable the graceful restart for a BGP neighbor.
        • Password: Enter the password used to reach the BGP neighbor.
        • Remote As: Specify the IP address of the remote AS.
        • TTL Security: Enter a minimum TTL (Time To Live) value for incoming IP packets received from peers in the remote AS. 
        • Update Source: Specify the IP address of the loopback interface so that BGP connections to the neighbor get sourced from the loopback IP.
      • Expand the Admin Shutdown section, and specify the following: 
        • Enable: Toggle this to True to enable administrative shutdown. You can shut down the BGP peer groups administratively, without removing the configuration from BGP.
        • Message: Enter the message you want to use when shutting down the BGP peer groups.
      • Expand the Neighbor IPv4 Unicast section, and specify the following:
        • Enabled: Toggle this to True to enable neighbor IPv4 unicast.
        • Next Hop Self: Toggle this to True to enable the net hop network address you want to add to the routing table to ensure that the network is reachable.
        • Soft Reconfiguration: Toggle this to True to generate inbound updates from a BGP neighbor, change, and activate BGP policies without clearing the BGP session. 
        • Weight Attribute: Enter a number for the weight that BGP will use to choose a path. Note that the path with the highest weight is preferred.
      • Expand the Timers section, and specify the following:
        • Advertise Interval: Enter the number of seconds that must elapse between an advertisement or a withdrawal of routes to a BGP peer.
        • Connect Time: Enter the number of seconds that the BGP peer is to stay connected.
        • Hold Time: Specify the number of seconds that may elapse between successive KEEPALIVE or UPDATE messages received from a BGP peer before the peer connection ends.
        • Keep Alive: Specify the time interval, in seconds, during which routes from a BGP peer are suppressed according to the setting for the hold time.
      • Click Add in the bottom-right corner of the section to add a neighbor parameter.
  • Expand the Peer Groups section, and do the following:
    • Click Add and enter the PEER GROUP NAME. 
      • In Description, enter the description of the BGP peer group.
      • In Graceful Restart, toggle this to True to enable and False to disable a graceful restart for a BGP neighbor.
      • In Password, enter the password used to reach the BGP neighbor.
      • In Remote As, specify the IP address of the remote AS.
      • In TTL Security, enter a minimum TTL (Time To Live) value for incoming IP packets received from peers in the remote AS. 
      • In Update Source, specify the IP address of the loopback interface so that BGP connections to the neighbor get sourced from the loopback IP.
      • Expand the Admin Shutdown section, and specify the following:
      • Expand the Neighbor IPv4 Unicast section, and specify the following:
      • Expand the Timers section, and specify the following:

      • Add a peer group by clicking Add in the bottom-right corner of the section.

      • Expand the Neighbor Param drop-down section, and do the following:
        • Enable: Toggle this to True to enable administrative shutdown. You can shut down the BGP peer groups administratively, without removing the configuration from BGP.
        • Message: Enter the message you want to use when shutting down the BGP peer groups.
        • Enabled: Toggle this to True to enable neighbor IPv4 unicast.
        • Next Hop Self: Enter the net hop network address you want to add to the routing table to ensure that the network is reachable.
        • Soft Reconfiguration: Toggle this to True to generate inbound updates from a BGP neighbor, change, and activate BGP policies without clearing the BGP session. 
        • Weight Attribute: Enter a number for the weight that BGP will use to choose a path. Note that the path with the highest weight is preferred.
        • Advertise Interval: Enter the number of seconds that must elapse between an advertisement or a withdrawal of routes to a BGP peer.
        • Connect Time: Enter the number of seconds that the BGP peer is to stay connected.
        • Hold Time: Specify the number of seconds that may elapse between successive KEEPALIVE or UPDATE messages received from a BGP peer before the peer connection ends.
        • Keep Alive: Specify the time interval, in seconds, during which routes from a BGP peer are suppressed according to the setting for the hold time.

5. Click Save & Close.


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