BGP Configurations

Each provider requires slightly different BGP configurations to announce my ASN upstream for my IP address range. All configurations are stored here as a reference.

BGP Server Configuration Files

• server1.frr.conf: Used by FRR running on Ubuntu 24.02.2. Server is announcing same IP address range that it hosts traffic for.
• server2.frr.conf: Used by FRR running on Ubuntu 24.02.2. Server is announcing same IP address range that it hosts traffic for.
• server3.frr.conf: Used by FRR running on Opnsense 25.4. Router is announcing an IP address range that it does not route traffic for.

Common Variables (with Examples)

• <local machine hostname> localhost.domain.com
• <my AS> 12345
• <remote AS> 54321
• <name of upstream provider> Upstream Provider BestHosting
• <my IP address to announce> 8.8.8.1
• <neighbor IP> 8.8.1.1
• <my IP range and subnet to announce> 8.8.8.0/24

Common BGP Commands

Show BGP Unicast Summary

sudo vtysh -c "show bgp ipv4 unicast summary"

Displays a summary of all BGP routes along with the state of BGP peers.
Use it as a quick check to verify that your BGP sessions are active and that routes are being exchanged.

Show Detailed Routing Information for an IP Prefix

sudo vtysh -c "show bgp ipv4 unicast xxx.xxx.xxx.0/24"

Replace xxx.xxx.xxx.0/24 with the IP address range being announced.
This command provides detailed routing information for the specific IP prefix.

Show Advertised Routes to a Specific BGP Neighbor

sudo vtysh -c "show ip bgp neighbors xxx.xxx.xxx.xxx advertised-routes"

Replace xxx.xxx.xxx.xxx with your upstream neighbor IP address.
This command shows the routes being advertised to a specified BGP neighbor and can help troubleshoot to ensure that the expected routes are shared with your upstream neighbor.