Hello all,
There is something really wired when playing DMVPN with backup NHS. It is a dmvpn with up to four hubs, i only want one hub up and running at a given time; eigrp is the routing protocol . so, i am using different priority to NHS towards each hub and only one NHS connection is allowed.
On the spoke, the tunnel is configured as such:
interface Tunnel10
description DMVPN
ip vrf forwarding FCA
bandwidth 1000
ip address 172.16.255.3 255.255.255.0
no ip redirects
ip mtu 1400
ip nhrp map multicast 192.168.110.254
ip nhrp map 172.16.255.254 192.168.110.254
ip nhrp map multicast 192.168.110.253
ip nhrp map 172.16.255.253 192.168.110.253
ip nhrp map multicast 192.168.110.252
ip nhrp map 172.16.255.252 192.168.110.251
ip nhrp map multicast 192.168.110.251
ip nhrp map 172.16.255.251 192.168.110.250
ip nhrp network-id 10
ip nhrp nhs 172.16.255.254 priority 1
ip nhrp nhs 172.16.255.253 priority 10
ip nhrp nhs 172.16.255.252 priority 20
ip nhrp nhs 172.16.255.251 priority 30
ip nhrp nhs fallback 30
ip nhrp shortcut
ip nhrp redirect
ip nhrp regis timeout 3
ip nhrp hold 10
ip tcp adjust-mss 1360
delay 10000
ip nhrp nhs cluster 0 max-connections 1
tunnel source GigabitEthernet0/1
tunnel mode gre multipoint
tunnel key 10
if-state nhrp
end
!
On the spoke, nhrp is performing as it should:
BNE_TEST#sh ip nhrp
172.16.255.251/32 (FCA) via 172.16.255.251
Tunnel10 created 00:36:02, never expire
Type: static, Flags:
NBMA address: 192.168.110.250
(no-socket)
172.16.255.252/32 (FCA) via 172.16.255.252
Tunnel10 created 00:36:02, never expire
Type: static, Flags:
NBMA address: 192.168.110.251
(no-socket)
172.16.255.253/32 (FCA) via 172.16.255.253
Tunnel10 created 00:36:02, never expire
Type: static, Flags:
NBMA address: 192.168.110.253
(no-socket)
172.16.255.254/32 (FCA) via 172.16.255.254
Tunnel10 created 00:36:02, never expire
Type: static, Flags: used
NBMA address: 192.168.110.254
!
as shown above, only one hub 172.16.255.254 with priority 1 is responding, while others show " no-socket"
but, the wired thing is :
the spoke has 4 eigrp neighbors:
BNE_TEST#sh ip eigrp vrf FCA nei
EIGRP-IPv4 Neighbors for AS(100) VRF(FCA)
2 172.16.255.252 Tu10 10 00:00:13
3 172.16.255.251 Tu10 11 00:00:26
1 172.16.255.253 Tu10 14 00:00:43
0 172.16.255.254 Tu10 14 00:38:53
only neighbor 172.16.255.254 stays nicely, other three are flapping all the time.
However, on the three alternative hubs, this spoke is never shown as an eigrp neighbor
According to labminute SEC0012, there should be only a single eigrp neighbor on the spoke:
.https://www.youtube.com/watch?v=17KQA-AntyE
Any idea ?
Thanks in advance
