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BGP Backdoor



Working on the simulation to show how BGP network x.x.x.x backdoor is working. So in the below example i have router which is configured with backdoor, when IGP (OSPF) is running i see this route in routing table, but from curiosity i shut that link to see if my route ( will show up in bgp table. It is not showing up? My understanding of the backdoor is that it will be advertised to eBGP peers once IGP link go down, also this is local subnet to this router so i imagined that would be advertised right away?  



R7#sh run | s bgp
router bgp 3
 bgp router-id
 bgp log-neighbor-changes
 network mask
 network mask backdoor
 network mask
 neighbor remote-as 1
 neighbor ebgp-multihop 2
 neighbor update-source Loopback0
 neighbor filter-list 1 out
 neighbor remote-as 4
 neighbor filter-list 1 out
 neighbor remote-as 5
 neighbor filter-list 1 out
R7#sh ip bgp nei adver
R7#sh ip bgp nei advertised-routes
BGP table version is 13, local router ID is
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter,
              x best-external, a additional-path, c RIB-compressed,
Origin codes: i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found

     Network          Next Hop            Metric LocPrf Weight Path
 *>                  0         32768 i
 *>                  0         32768 i
 *>                  0         32768 i

Total number of prefixes 3


R7#sh ip int br | e una
Interface                  IP-Address      OK? Method Status                Protocol
Ethernet0/0        YES manual up                    up  
Serial2/0          YES manual up                    up  
Serial2/1          YES manual up                    up  
Loopback0            YES manual up                    up  
Loopback1              YES manual up                    up  
Loopback3              YES manual up                    up  
Loopback10          YES manual up                    up  
Loopback11             YES manual up                    up 

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