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I have this rather basic setup with 3 routers running BGP, each has Loopback int configured. Is there an extra step required for R2 to ping R4 Loopback interface despite it's being advertised?

enter image description here

R2#sh run | s bgp
router bgp 65001
 bgp log-neighbor-changes
 neighbor 11.0.0.1 remote-as 65001
 neighbor 22.0.0.2 remote-as 65002
 !
 address-family ipv4
  network 172.17.0.1 mask 255.255.255.255
  neighbor 11.0.0.1 activate
  neighbor 22.0.0.2 activate
 exit-address-family

R3#sh run | s bgp
router bgp 65002
 bgp log-neighbor-changes
 neighbor 22.0.0.1 remote-as 65001
 neighbor 33.0.0.2 remote-as 65002
 !
 address-family ipv4
  neighbor 22.0.0.1 activate
  neighbor 33.0.0.2 activate
 exit-address-family

R4#sh run | s bgp
router bgp 65002
 bgp log-neighbor-changes
 neighbor 33.0.0.1 remote-as 65002
 !
 address-family ipv4
  network 172.19.0.1 mask 255.255.255.255
  neighbor 33.0.0.1 activate
 exit-address-family



Gateway of last resort is not set

      11.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C        11.0.0.0/30 is directly connected, Ethernet0/0
L        11.0.0.2/32 is directly connected, Ethernet0/0
      22.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C        22.0.0.0/30 is directly connected, Ethernet0/1
L        22.0.0.1/32 is directly connected, Ethernet0/1
      172.16.0.0/32 is subnetted, 1 subnets
B        172.16.0.1 [200/0] via 11.0.0.1, 00:16:57
      172.17.0.0/32 is subnetted, 1 subnets
C        172.17.0.1 is directly connected, Loopback1
      172.19.0.0/32 is subnetted, 1 subnets
B        172.19.0.1 [20/0] via 22.0.0.2, 01:13:24

R2#sh bgp ipv4 unicast
BGP table version is 16, local router ID is 172.17.0.1
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
 *>i 172.16.0.1/32    11.0.0.1                 0    100      0 i
 *>  172.17.0.1/32    0.0.0.0                  0         32768 i
 *>  172.19.0.1/32    22.0.0.2                               0 65002 i
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  • Can you post full sanitized configs for all of the routers?
    – Jesse P.
    Commented Apr 8, 2021 at 12:19
  • 1
    You are not advertising any networks in BGP.
    – Ron Maupin ♦
    Commented Apr 8, 2021 at 12:24
  • 3
    @JesseP., there are no network statements or redistribution commands under BGP to actually advertise any networks.
    – Ron Maupin ♦
    Commented Apr 8, 2021 at 12:42
  • 1
    thanks for pointing me in the right direction, I have added network 22.0.0.0 mask 255.255.255.252 network 33.0.0.0 mask 255.255.255.252 on R3 and I'm able to ping remote nets, thanks
    – imperato
    Commented Apr 9, 2021 at 9:38
  • 1
    @imperato As a side note, you really shouldn't be using public addresses for your internal BGP peerings because now you e effectively blackholed traffic to whoever those blocks belong to, should you ever need to access them publicly.
    – Jesse P.
    Commented Apr 9, 2021 at 12:26

1 Answer 1

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thanks for pointing me in the right direction, I have added network 22.0.0.0 mask 255.255.255.252 network 33.0.0.0 mask 255.255.255.252 on R3 and I'm able to ping remote nets, thanks

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