Description
This article looks at the effect of BGP synchronisation rule on learning BGP routes from the BGP peer. It basically states that unless and until a route is present in IGP table, the FortiGate will not advertise BGP route to the BGP peer. Nor will it install the BGP route received from the peer into the routing table. By default, the synchronization is disabled.
Solution
Configuration CLI
config router bgp
set as 12849
set router-id 213.57.1.254
set synchronization enable
config neighbor
edit "213.57.1.253"
set remote-as 12849
next
end
end
Verification of configuration and troubleshooting
FGT # get router info bgp summary
BGP router identifier 213.57.1.254, local AS number 12849
BGP table version is 5
1 BGP AS-PATH entries
0 BGP community entries
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
213.57.1.253 4 12849 5075 2337 4 0 0 00:06:24 1
Total number of neighbors 1
FGT # get router info bgp neighbor 213.57.1.253 received-routes
BGP table version is 13, local router ID is 213.57.1.254
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*>i0.0.0.0/0 213.57.1.253 100 0 i
Default route 0.0.0.0/0 is being received from the peer. This route is not previously present in routing table. It is not in the IGP table.
FGT# get router info routing-table all
Codes: K - kernel, C - connected, S - static, R - RIP, B - BGP
O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
> - selected route, * - FIB route, p - stale info
The received route not present in the routing table.
