[j-nsp] Hidden iBGP Route if OSPF no-summaries is configured

[alaerte vidali]

Hi,

I am getting the following behavior: an iBGP route is hidden on local router
if advertising iBGP router is ABR OSPF NSSA with no-summaries configured.
Removing the "no-summaries"  on neighbor results the route is installed.

Now I am trying to understand why so.

Any feedback appreciated.


Here some commands showing it:

with no-summary

root at R1_P1_P2# run show route 10.200.0.0/16 hidden

10.200.0.0/16       [BGP/170] 02:40:40, localpref 100, from 10.200.11.1
                      AS path: I
                      Unusable


root at R1_P1_P2# run show route 10.200.0.0/16 hidden detail

inet.0: 32 destinations, 38 routes (31 active, 0 holddown, 1 hidden)
10.200.0.0/16 (1 entry, 0 announced)
         BGP    Preference: 170/-101
                Next hop type: Unusable
                Next-hop reference count: 1
                State: <Hidden Int Ext>
                Local AS: 65412 Peer AS: 65412
                Age: 2:40:44
                Task: BGP_65412.10.200.11.1+58281
                AS path: I
                Accepted
                Localpref: 100
                Router ID: 10.200.11.1


root at R1_P1_P2# run show route 0.0.0.0/0 detail

inet.0: 32 destinations, 38 routes (31 active, 0 holddown, 1 hidden)
0.0.0.0/0 (1 entry, 1 announced)
        *OSPF   Preference: 10
                Next hop type: Router, Next hop index: 639
                Next-hop reference count: 35
                Next hop: 10.200.4.10 via fxp0.13, selected
                State: <Active Int>
                Local AS: 65412
                Age: 1:49     Metric: 20
                Area: 0.0.0.1
                Task: OSPF
                Announcement bits (2): 0-KRT 4-Resolve tree 1
                AS path: I


root at R1_P1_P2# run show route received-protocol bgp 10.200.11.1 hidden
detail

inet.0: 32 destinations, 38 routes (31 active, 0 holddown, 1 hidden)
  10.200.0.0/16 (1 entry, 0 announced)
     Accepted
     Nexthop: 10.200.11.1
     Localpref: 100
     AS path: I


without no-summary on neighbor:


root at R1_P1_P2# run show route 10.200.0.0/16 detail

inet.0: 46 destinations, 52 routes (46 active, 0 holddown, 0 hidden)
10.200.0.0/16 (1 entry, 1 announced)
        *BGP    Preference: 170/-101
                Next hop type: Indirect
                Next-hop reference count: 21
                Source: 10.200.11.1
                Next hop type: Router, Next hop index: 639
                Next hop: 10.200.4.10 via fxp0.13, selected
                Protocol next hop: 10.200.11.1

root at R1_P1_P2# run show route 0.0.0.0/0 detail

inet.0: 46 destinations, 52 routes (46 active, 0 holddown, 0 hidden)
0.0.0.0/0 (1 entry, 1 announced)
        *OSPF   Preference: 150
                Next hop type: Router, Next hop index: 639
                Next-hop reference count: 60
                Next hop: 10.200.4.10 via fxp0.13, selected
                State: <Active Int Ext>
                Local AS: 65412
                Age: 36:23     Metric: 10     Tag: 0
                Task: OSPF
                Announcement bits (2): 0-KRT 4-Resolve tree 1
                AS path: I