- By default, the 'capability-route-refresh' is enabled under the BGP neighbor.
config router bgp
config neighbor
edit <BGP-NEIGHBOR-IP>
set capability-route-refresh enable
next
end
end
- Route refresh capability must have been negotiated in the BGP OPEN message when the BGP session is established.
vdom2 # get router info bgp neighbors 10.144.127.1 | grep capabilities -A 1
Neighbor capabilities:
Route refresh: advertised and received (old and new)
If the remote peer is not configured for Route Refresh, FortiGate will not show 'received'.
vdom2 # get router info bgp neighbors 10.144.127.1 | grep capabilities -A 1
Neighbor capabilities:
Route refresh: advertised
- Command to perform the route refresh.
Fortigate# execute router clear bgp ip <neighbor_ip> [in|out]
- out: Resend all routes to the neighbor in the BGP UPDATE message without resetting the connection. Recommended when changing outbound policy. ROUTE-REFRESH is not required when sending outbound routes.
- in : Sends a ROUTE-REFRESH request message to the BGP neighbor so that neighbor re-sends all BGP routes in the BGP UPDATE message. Recommended when changing inbound policy.
Ensure that 'soft-reconfiguration' is disabled.
If soft-reconfiguration is enabled, FortiGate will store a local unmodified database of all routes received from the BGP neighbor and will use this database when performing 'execute router clear bgp ip <neighbor_ip> in'. FortiGate does not send any ROUTE-REFRESH message for ipv4 address family in this case.
The end result of a soft reset is similar with or without soft-reconfiguration enabled, but when enabled the FortiGate stores an additional copy of the database, which consumes additional memory. See the article 'Technical Tip: BGP - Soft Reconfiguration vs. Route Refresh'.
config router bgp
config neighbor
edit <BGP-NEIGHBOR-IP>
set capability-route-refresh enable
set soft-reconfiguration disable
next
end
end
Note:
Changing bgp capability configuration will hard reset the bgp neighbor peering and impact data traffic. Changing soft-reconfiguration configuration does not hard reset the bgp peering.
- FortiGate does not support the BGP capability code 70 'Enhanced route refresh capability' [RFC7313].
If the BGP neighbor (another vendor device) advertises that capability this does not prevent BGP negotiation from succeeding if FortiGate is using the default configuration 'set ignore-optional-capability enable'.
config router bgp
set ignore-optional-capability enable
end
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