Configuration queries on BGP

+Is it possible to configure 2 different AS in gobal routing table?

+When 2 static routes have same next-hop, which exit interface would be preferred?

-->Is it possible to configure 2 different AS in global routing table?

Solution:

Can configure multiple routing instances (VRFs) on the Juniper MX router, each with a different AS number.

EXAMPLE:

routing-instances {

   AS500 {

       instance-type vrf;

       route-distinguisher 500:1;

       vrf-target target:500:500;

       protocols {

           bgp {

               local-as 500;

           }

       }

   }

   AS234 {

       instance-type vrf;

       route-distinguisher 234:6;

       vrf-target target:234:234;

       protocols {

           bgp {

               local-as 234;

           }

       }

   }

}

+Other way is to use Logical-systems to use different AS as below example:

logical-systems {

   LS1 {

       autonomous-system 123;

       protocols {

           bgp {

               group peer1 {

                   type external;

                   peer-as 234;

                   neighbor 192.168.1.2;

               }

           }

       }

   }

   LS2 {

       autonomous-system 900;

       protocols {

           bgp {

               group peer2 {

                   type external;

                   peer-as 100;

                   neighbor 192.168.2.2;

               }

           }

       }

   }

}

-->When 2 static routes have same next-hop, which exit interface would be preferred?

Solution:

Qualified-next-hop is used in this scenario.

Please refer the below document for more information:

https://www.juniper.net/documentation/us/en/software/junos/static-routing/topics/topic-map/static-route-prefer-qualified-next-hop.html

If Qualified-next-hop is not preferred, lower AD value is considered which is not encouraged behaviour.