DMVPN EIGRP issue

[Pushpa Ranathunga]

Hi

I am having DMVPN with EIGRP

But i am having the following EIGRP error

"*Mar  1 00:27:15.119: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 90: Neighbor 192.168.1.3 (Tunnel0) is down: retry limit exceeded"

Following my hub config :

ip address 192.168.1.1 255.255.255.0
ip nhrp authentication cisco123
ip nhrp network-id 1
tunnel source FastEthernet0/0
tunnel mode gre multipoint

Following is my spoke config :

ip address 192.168.1.3 255.255.255.0
ip nhrp authentication cisco123
ip nhrp map 192.168.1.1 200.200.200.1
ip nhrp map multicast 200.200.200.1
ip nhrp network-id 1
ip nhrp nhs 192.168.1.1
tunnel source FastEthernet0/0
tunnel destination 200.200.200.1

Please help to solve this issue :)

[Rich Uline]

Pushpa,

A common issue when setting up a tunnel is that the tunnel destination is learned via the tunnel interface. To prevent this, ensure you have a static route with a low AD for the tunnel destination. What does your routing configuration look like?

[Pushpa Ranathunga]

Hi Rich,

My connectivity is simple since all of those are connected to a L2 switch as follows

So i do not think i need to add routes since all of interfaces are in a single subnet

Further to that, i can ping to the tunnel interfaces as well

[Pushpa Ranathunga]

Hi

I sorted this by myself

Issue was, i had not put the command "no ip spli horizon", after putting that, it was OK

However i have two concerns

1. I did not want spoke to spoke to communication. So i missed that command purposefully. I am wondering y the neighbor relationship not formed without "no ip split horizon" command

2. I had to shut and no shut tunnel interfaces. Y is that ???

[Shebin]

Split horizon are enabled by default to prevent looping in Enhanced Interior Gateway Protocol... all you're spokes multicast traffic are mapped to HUB underla network , so for say example R1 sends hello to Hub ,Hub will accept that packet and will not retransmit to the same Link from where he got the packet ,and if Hub will not retransmit it ,the hello packets will not reach to other spokes and will not form neighborship.....

Note:For neighbor-ship between spokes you should have Phase 2 or Phase running