Hi folks,
I have an issue where I have a DMVPN set up with EIGRP. I have a secondary tunnel configured with one of the spokes in the primary tunnel is the hub of the secondary tunnel. Here are the configurations I have:
Router A
ROUTER_A#sh run int t0
Building configuration...
Current configuration : 533 bytes
!
interface Tunnel0
bandwidth 8000
ip address 10.x.x.12 255.255.255.240
no ip redirects
ip mtu 1446
no ip next-hop-self eigrp 1
ip flow ingress
ip flow egress
ip nhrp authentication cisco123
ip nhrp map multicast dynamic
ip nhrp network-id 8
ip nhrp holdtime 600
ip nhrp redirect
no ip route-cache cef
no ip route-cache
ip tcp adjust-mss 1446
no ip split-horizon eigrp 1
delay 1
tunnel source GigabitEthernet0/0
tunnel mode gre multipoint
tunnel key 67132
tunnel protection ipsec profile strong_prof shared
!
end
ROUTER_A#sh run int t1
Building configuration...
Current configuration : 577 bytes
!
interface Tunnel1
bandwidth 4000
ip address 10.x.x.66 255.255.255.240
no ip redirects
ip mtu 1446
ip flow ingress
ip flow egress
ip nhrp authentication cisco123
ip nhrp map 10.x.x.65 63.245.66.202
ip nhrp map multicast 63.245.66.202
ip nhrp network-id 18
ip nhrp holdtime 600
ip nhrp nhs 10.x.x.65
ip nhrp shortcut
ip nhrp redirect
ip virtual-reassembly
ip tcp adjust-mss 1446
no ip split-horizon eigrp 2
delay 2000
shutdown
tunnel source GigabitEthernet0/0
tunnel mode gre multipoint
tunnel key 12133
tunnel protection ipsec profile strong_prof2
!
end
ROUTER_A#sh run | sec router eigrp
router eigrp 1
network 10.x.x.0 0.0.0.15
network 10.3.0.0 0.0.0.255
router eigrp 2
network 10.x.x.64 0.0.0.15
network 10.3.0.0 0.0.0.255
Router B
ROUTER_B#sh run int t0
Building configuration...
Current configuration : 608 bytes
!
interface Tunnel0
bandwidth 8000
ip address 10.x.x.11 255.255.255.240
no ip redirects
ip mtu 1446
ip flow ingress
ip flow egress
ip nhrp authentication cisco123
ip nhrp map multicast 81.91.242.68
ip nhrp map 10.x.x.12 81.91.242.68
ip nhrp network-id 8
ip nhrp holdtime 600
ip nhrp nhs 10.x.x.12
ip nhrp shortcut
ip nhrp redirect
ip virtual-reassembly
no ip route-cache cef
no ip route-cache
ip tcp adjust-mss 1446
no ip split-horizon eigrp 1
delay 1
tunnel source FastEthernet0/0/0
tunnel mode gre multipoint
tunnel key 67132
tunnel protection ipsec profile strong_prof shared
!
end
ROUTER_B#sh run int t1
Building configuration...
Current configuration : 521 bytes
!
interface Tunnel1
bandwidth 4000
ip address 10.x.x.65 255.255.255.240
no ip redirects
ip mtu 1446
no ip next-hop-self eigrp 2
ip flow ingress
ip flow egress
ip nhrp authentication cisco123
ip nhrp map multicast dynamic
ip nhrp network-id 18
ip nhrp holdtime 600
ip nhrp redirect
ip virtual-reassembly
ip tcp adjust-mss 1446
no ip split-horizon eigrp 2
delay 2000
shutdown
tunnel source FastEthernet0/0/0
tunnel mode gre multipoint
tunnel key 12133
tunnel protection ipsec profile strong_prof2
!
end
ROUTER_B#sh run | sec router eigrp
router eigrp 1
network 10.x.x.0 0.0.0.15
redistribute static route-map static_to_eigrp
router eigrp 2
network 10.x.x.64 0.0.0.15
redistribute static route-map static_to_eigrp
Router C/D/E
ROUTER_C#sh run int t0
Building configuration...
Current configuration : 550 bytes
!
interface Tunnel0
bandwidth 8000
ip address 10.x.x.13 255.255.255.240
no ip redirects
ip mtu 1446
ip flow ingress
ip nhrp authentication cisco123
ip nhrp map 10.x.x.12 81.91.242.68
ip nhrp map multicast 81.91.242.68
ip nhrp network-id 8
ip nhrp holdtime 600
ip nhrp nhs 10.x.x.12
ip nhrp shortcut
ip nhrp redirect
ip virtual-reassembly
ip tcp adjust-mss 1446
no ip split-horizon eigrp 1
delay 1
tunnel source FastEthernet0/0/1
tunnel mode gre multipoint
tunnel key 67132
tunnel protection ipsec profile strong_prof shared
!
end
ROUTER_C#sh run int t1
Building configuration...
Current configuration : 560 bytes
!
interface Tunnel1
bandwidth 4000
ip address 10.x.x.67 255.255.255.240
no ip redirects
ip mtu 1446
ip flow ingress
ip nhrp authentication cisco123
ip nhrp map multicast 63.245.66.202
ip nhrp map 10.x.x.65 63.245.66.202
ip nhrp network-id 18
ip nhrp holdtime 600
ip nhrp nhs 10.x.x.65
ip nhrp shortcut
ip nhrp redirect
ip virtual-reassembly
ip tcp adjust-mss 1446
no ip split-horizon eigrp 2
delay 2000
shutdown
tunnel source FastEthernet0/0/1
tunnel mode gre multipoint
tunnel key 12133
tunnel protection ipsec profile strong_prof2
!
end
ROUTER_C#sh run | sec router eigrp
router eigrp 1
network 10.x.x.0 0.0.0.15
network 10.4.0.0 0.0.0.255
redistribute static route-map STATIC_TO_OSPF
router eigrp 2
network 10.x.x.64 0.0.0.15
network 10.4.0.0 0.0.0.255
redistribute static route-map STATIC_TO_OSPF
Now what happens is that when I shut down the tunnel0 interface on RouterA, everything fails over to the tunnel1 interfaces. When I bring back up the tunnel0 on RouterA, everything keeps using the tunnel1 interfaces. When I check show ip nhrp detail and sh ip eigrp topology/neighbours, its as if the other tunnel interface doesn't exist anymore.
How can I get this to fail back over properly. I thought of something just now that isn't configured the way I have it in my diagram. Router A is configured as a spoke in the backup tunnels. Do you think that this could have been the source of my problem? I can't test this until tomorrow morning as the maintenance window is gone but I'd appreciate any ideas until then
Cheers,
Xavier
