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Why not advertised via BGP?

I have a loopback configured (1)

I have advertised the same prefix in BGP. (2)

The BGP neighbor in question is healthy with 159 routes received (3)

Why is this prefix not advertised via BGP? (4) 


2023-12-16 18h27m02 Why not advertised via BGP.png


1 Solution

Each VRF routes are isolated so if your route is in VRF7, it will not be present in BGP databse/table on VRF1. You may configure VRF route leaking



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My bet is since you are using another interface as update-source in BGP that you need to advertised that network, into BGP, since u are using it as next-hop-self for all network advertised.


Thanks @funkylicious. and can ping each other. They are the 2 ends of the healthy BGP peer.
Below is the BGP summary from the other (hub) side.


2023-12-17 08h55m28 hub get bgp summary.png

I changed the router ID from to the loopback no change in outcome though.
Appreciate the suggestion though.... please share if any more ideas come!



"This command is not used to enable BGP on interfaces (as a matter of fact, there is no such concept in BGP, as there is in IGPs), but it is used to inject routes from the routing table to the BGP table so they can be advertised to BGP peers. For this to happen, an exact route for the prefix that needs to be advertised should be installed in the routing table on the BGP-speaking router."

This condition is met I think. My loopback address is and advertised as such


Post2: - More of less the same thing but discusses set network-import-check disable.


Thanks though...


Loopback interfaces are in "connected" routes just like any other interfaces. You have to redistribute them into BGP.

   config redistribute "connected"
       set status enable



Thanks @Toshi_Esumi 
Is this the only way to advertise into BGP?
config network /set prefix as in screenshot does nothing?
Thanks again


I'm talking about "redistribution" from connected routes into BGP. Not "advertisement", which is inside of BGP domain.
If you run "get router info bgp network", you wouldn't see the loopback interface IP in BGP table. If it's not in the table, you would never be able to "advertise" whatever the command, like "config network", you use. Because it's not there to be advertised.




Hold on. Looks like I was wrong. When I set the network statement without re-distribution, it shows in my BGP table. So that's not the cause.

fg40f-utm (bgp) # show
config router bgp
   config network
       edit 1
           set prefix
  config redistribute "connected"
fg40f-utm (root) # show sys int loop99
config system interface
   edit "loop99"
       set vdom "root"
       set ip
       set type loopback
       set snmp-index 32

fg40f-utm (root) # get router info bgp network
                                100  32768        0 i <-/1>



@Toshi_Esumi really appreciate your help.

I wonder if you could help clarify the difference between advertise and redistribute.
I am familiar with BGP as implemented by cisco devices.

I was assuming that Fortigate would mean the same thing.

Let us establish what we do agree on:

A1. Any BGP implementation has a database of routes.

A2. This database of routes is exchanged with BGP neighbors subject to any rules/config e.g. filters, route-maps etc. etc.

A3. config redistribute connected This command injects all connected subnets into the aforementioned database (Assuming the interfaces are up). Such injected routes then will be propagated with all neighbors (subject to filtering/route-map manipulation etc as mentioned).

A4. set prefix in context of your example above. IF this network is in the main routing table already then it will be injected into the BGP database and propagated as per A3.


Grateful if you would like to comment on the above assumptions/statements.


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