DMVPN Reference

Configuration.
!HUB:
!
!!ISAKMP Phase 1
crypto isakmp policy 10
 authentication pre-share
 hash md5
 encr 3des
 group 5
!
!!Wildcard key
crypto isakmp key Password123 address 0.0.0.0
!
crypto ipsec transform-set DMVPN_TRANSFORM_SET esp-des esp-md5-hmac
mode transport
!
!!IPSec phase 2
crypto ipsec profile DMVPN_PROFILE
 set transform-set DMVPN_TRANSFORM_SET
!
interface Tunnel0
 ip address 10.255.255.5 255.255.255.0
 no ip redirects
 ip mtu 1400
 ip nhrp authentication Password123
!!Hub is dynamic
 ip nhrp map multicast dynamic
 ip nhrp network-id 99
 ip tcp adjust-mss 1360
 no ip split-horizon eigrp 999
 delay 1000
!!Enable DMVPN Phase 3 redirection on Hub
 ip nhrp redirect
 tunnel source FastEthernet0/1
 tunnel mode gre multipoint
 tunnel key 1
 tunnel protection ipsec profile DMVPN_PROFILE
!
!
############################################
!
!
!SPOKE:
!
crypto isakmp policy 10
 encr 3des
 hash md5
 authentication pre-share
 group 5
!
crypto isakmp key Password123 address 0.0.0.0 0.0.0.0
!
crypto ipsec transform-set DMVPN_TRANSFORM_SET esp-des esp-md5-hmac
!
crypto ipsec profile DMVPN_PROFILE
 set transform-set DMVPN_TRANSFORM_SET
!
interface Tunnel0
 ip address 10.255.255.1 255.255.255.0
 no ip redirects
 ip mtu 1400
 ip nhrp authentication Password123
!!Map Tunnel IP to Outside IP
 ip nhrp map 10.255.255.5 10.0.125.5
!!Multicast map to the Hubs Outside IP.
 ip nhrp map multicast 10.0.125.5
 ip nhrp network-id 99
!!NHS should point to the Hub’s tunnel IP
 ip nhrp nhs 10.255.255.5
!! Enable DMVPN Phase 3 shortcut and redirection
 ip nhrp shortcut
 ip nhrp redirect
 ip tcp adjust-mss 1360
 delay 1000
 tunnel source Loopback0
 tunnel mode gre multipoint
 tunnel key 1
 tunnel protection ipsec profile DMVPN_PROFILE
!
!

Troubleshooting and Verification.
sh ip nhrp
sh ip nhrp nhs detail
sh crypto isakmp sa
sh crypto ipsec sa
sh dmvpn
debug crypto isakmp
debug crypto ipsec
debug nhrp
debug dmvpn all nhrp