FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
Article Id 308857
Description This article explains how the BGP routes propagate, how different routes are manipulated, and what commands are used in these locations.
Scope FortiGate.

Below is a basic flow diagram of how BGP route propagation is done:




BGP router is receiving BGP routes from its neighbor 1.


  1. If 'soft-reconfiguration' is enabled, it is possible to view the received route, before they reach the inbound policy.


config neighbor
   edit ""
      set soft-reconfiguration enable


  1. Inbound policy is where route-maps are applied for incoming routes from the neighbor.
  2. After applying inbound policies, routes are sent to BGP table.
  3. The Best routes are sent to the Routing table.
  4. For outgoing routes,  it is possible to add outbound policies via route-maps and filtered routes will reach the other BGP neighbor 2.


Different commands are used in places in the flow chart. Commands in {A, B, C, D, E} locations on the diagram will be shown below.


[A] -  get router info bgp neighbors <neighbor-IP> received-routes

[B] -  get router info bgp neighbors <neighbor-IP> routes

[C] -  get router info bgp network

       get router info bgp network <prefix>

[D] -  get router info bgp neighbors <neighbor-IP> advertised-routes

[E] -  get router info routing-table all

       get router info routing-table database

       get router info routing-table details <network>


Outputs of these commands can be seen from this related article:

Technical Tip: Use case of a Local preference and AS path prepending for route manipulation in BGP