Vyatta NOS documentation

Learn how to install, configure, and operate Vyatta Network Operating System (Vyatta NOS), which helps to drive our virtual networking and physical platforms portfolio.

Basic eBGP configuration

In this section, you configure eBGP on the routers labeled R1 and R4 in the reference network diagram. Router R1 is peering with an eBGP neighbor that is configured to be in AS 200 and router R4 is peering with an eBGP neighbor in AS 300.

In this example, the eBGP peering connections are established between eBGP neighbors using the physical interface IP addresses. This is a common configuration for eBGP peers. If the link between the peers goes down, the peering relationship should also go down since there is no redundancy.

After the basic eBGP configuration has been completed, the network should look as shown in the following figure.

Figure 1. Basic eBGP configuration

This example assumes the following:

  • The configuration in the preceding example has already been performed.
  • The eBGP peers connecting to R1 and R4 have been properly configured for BGP.

To create a basic eBGP configuration, perform the following steps in configuration mode.

Table 1. Basic eBGP configuration

Router

Step

Commands

R1

Create an eBGP peer for R1. The peer is an eBGP peer because it resides in a different AS than this router.

vyatta@R1# set protocols bgp 100 neighbor 88.88.88.2 remote-as 200

R1

Activate the neighbor for the IPv4 unicast address family to enable the exchange IPv4 unicast routes.

vyatta@R1# set protocols bgp 100 neighbor 88.88.88.2 address-family ipv4-unicast

R1

Commit the configuration.

vyatta@R1# commit

R1

Display the configuration.

vyatta@R1# show protocols
 protocols {
      bgp 100 {
               neighbor 88.88.88.2 {
                       address-family {
                               ipv4-unicast
                       }
                       remote-as 200
               }
       }

R4

Create an eBGP peer for R4. The peer is an eBGP peer because it resides in a different AS than this router.

vyatta@R4# set protocols bgp 100 neighbor 99.99.99.2 remote-as 300 

R4

Activate the neighbor for the IPv4 unicast address family to enable the exchange IPv4 unicast routes.

vyatta@R4# set protocols bgp 100 neighbor 99.99.99.2 address-family ipv4-unicast

R4

Commit the configuration.

vyatta@R4# commit

R4

Commit the configuration.

vyatta@R4# show protocols
 protocols {
      bgp 100 {
               neighbor 99.99.99.2 {
                       address-family {
                               ipv4-unicast
                       }
                       remote-as 300
               }
       }