Hello everyone
I got a problem with my DMVPN. Spoke is behind a NAT device. x.x.x.x is an public IP address which hub uses. I don't know why it discovered that the hub is also inside a NAT device. And after it sends a packet using port 4500, the received packet from hub was not using port 4500 but 500. I'm confused now. Any advise would be much appreciated.
*Sep 10 08:56:02 UTC: ISAKMP:(0): beginning Main Mode exchange
*Sep 10 08:56:02 UTC: ISAKMP:(0): sending packet to x.x.x.x my_port 500 peer_port 500 (I) MM_NO_STATE
*Sep 10 08:56:02 UTC: ISAKMP:(0):Sending an IKE IPv4 Packet.
*Sep 10 08:56:02 UTC: ISAKMP (0): received packet from x.x.x.x dport 500 sport 500 Global (I) MM_NO_STATE
*Sep 10 08:56:02 UTC: ISAKMP:(0):Input = IKE_MESG_FROM_PEER, IKE_MM_EXCH
*Sep 10 08:56:02 UTC: ISAKMP:(0):Old State = IKE_I_MM1 New State = IKE_I_MM2
*Sep 10 08:56:02 UTC: ISAKMP:(0): processing SA payload. message ID = 0
*Sep 10 08:56:02 UTC: ISAKMP:(0): processing vendor id payload
*Sep 10 08:56:02 UTC: ISAKMP:(0): vendor ID seems Unity/DPD but major 69 mismatch
*Sep 10 08:56:02 UTC: ISAKMP (0): vendor ID is NAT-T RFC 3947
*Sep 10 08:56:02 UTC: ISAKMP:(0):found peer pre-shared key matching
*Sep 10 08:56:02 UTC: ISAKMP:(0): local preshared key found
*Sep 10 08:56:02 UTC: ISAKMP : Scanning profiles for xauth ...
*Sep 10 08:56:02 UTC: ISAKMP:(0):Checking ISAKMP transform 1 against priority 1 policy
*Sep 10 08:56:02 UTC: ISAKMP: encryption 3DES-CBC
*Sep 10 08:56:02 UTC: ISAKMP: hash MD5
*Sep 10 08:56:02 UTC: ISAKMP: default group 1
*Sep 10 08:56:02 UTC: ISAKMP: auth pre-share
*Sep 10 08:56:02 UTC: ISAKMP: life type in seconds
*Sep 10 08:56:02 UTC: ISAKMP: life duration (VPI) of 0x0 0x1 0x51 0x80
*Sep 10 08:56:02 UTC: ISAKMP:(0):atts are acceptable. Next payload is 0
*Sep 10 08:56:02 UTC: ISAKMP:(0):Acceptable atts:actual life: 0
*Sep 10 08:56:02 UTC: ISAKMP:(0):Acceptable atts:life: 0
*Sep 10 08:56:02 UTC: ISAKMP:(0):Fill atts in sa vpi_length:4
*Sep 10 08:56:02 UTC: ISAKMP:(0):Fill atts in sa life_in_seconds:86400
*Sep 10 08:56:02 UTC: ISAKMP:(0):Returning Actual lifetime: 86400
*Sep 10 08:56:02 UTC: ISAKMP:(0)::Started lifetime timer: 86400.
*Sep 10 08:56:02 UTC: ISAKMP:(0): processing vendor id payload
*Sep 10 08:56:02 UTC: ISAKMP:(0): vendor ID seems Unity/DPD but major 69 mismatch
*Sep 10 08:56:02 UTC: ISAKMP (0): vendor ID is NAT-T RFC 3947
*Sep 10 08:56:02 UTC: ISAKMP:(0):Input = IKE_MESG_INTERNAL, IKE_PROCESS_MAIN_MODE
*Sep 10 08:56:02 UTC: ISAKMP:(0):Old State = IKE_I_MM2 New State = IKE_I_MM2
*Sep 10 08:56:02 UTC: ISAKMP:(0): sending packet to x.x.x.x my_port 500 peer_port 500 (I) MM_SA_SETUP
*Sep 10 08:56:02 UTC: ISAKMP:(0):Sending an IKE IPv4 Packet.
*Sep 10 08:56:02 UTC: ISAKMP:(0):Input = IKE_MESG_INTERNAL, IKE_PROCESS_COMPLETE
*Sep 10 08:56:02 UTC: ISAKMP:(0):Old State = IKE_I_MM2 New State = IKE_I_MM3
*Sep 10 08:56:02 UTC: ISAKMP (0): received packet from x.x.x.x dport 500 sport 500 Global (I) MM_SA_SETUP
*Sep 10 08:56:02 UTC: ISAKMP:(0):Input = IKE_MESG_FROM_PEER, IKE_MM_EXCH
*Sep 10 08:56:02 UTC: ISAKMP:(0):Old State = IKE_I_MM3 New State = IKE_I_MM4
*Sep 10 08:56:02 UTC: ISAKMP:(0): processing KE payload. message ID = 0
*Sep 10 08:56:02 UTC: ISAKMP:(0): processing NONCE payload. message ID = 0
*Sep 10 08:56:02 UTC: ISAKMP:(0):found peer pre-shared key matching x.x.x.x
*Sep 10 08:56:02 UTC: ISAKMP:(2746): processing vendor id payload
*Sep 10 08:56:02 UTC: ISAKMP:(2746): vendor ID is Unity
*Sep 10 08:56:02 UTC: ISAKMP:(2746): processing vendor id payload
*Sep 10 08:56:02 UTC: ISAKMP:(2746): vendor ID is DPD
*Sep 10 08:56:02 UTC: ISAKMP:(2746): processing vendor id payload
*Sep 10 08:56:02 UTC: ISAKMP:(2746): speaking to another IOS box!
*Sep 10 08:56:02 UTC: ISAKMP:received payload type 20
*Sep 10 08:56:02 UTC: ISAKMP (2746): NAT found, both nodes inside NAT
*Sep 10 08:56:02 UTC: ISAKMP:received payload type 20
*Sep 10 08:56:02 UTC: ISAKMP (2746): My hash no match - this node inside NAT
*Sep 10 08:56:02 UTC: ISAKMP:(2746):Input = IKE_MESG_INTERNAL, IKE_PROCESS_MAIN_MODE
*Sep 10 08:56:02 UTC: ISAKMP:(2746):Old State = IKE_I_MM4 New State = IKE_I_MM4
*Sep 10 08:56:02 UTC: ISAKMP:(2746):Send initial contact
*Sep 10 08:56:02 UTC: ISAKMP:(2746):SA is doing pre-shared key authentication using id type ID_IPV4_ADDR
*Sep 10 08:56:02 UTC: ISAKMP (2746): ID payload
next-payload : 8
type : 1
address : 192.168.1.101
protocol : 17
port : 0
length : 12
*Sep 10 08:56:02 UTC: ISAKMP:(2746):Total payload length: 12
*Sep 10 08:56:02 UTC: ISAKMP:(2746): sending packet to x.x.x.x my_port 4500 peer_port 4500 (I) MM_KEY_EXCH
*Sep 10 08:56:02 UTC: ISAKMP:(2746):Sending an IKE IPv4 Packet.
*Sep 10 08:56:02 UTC: ISAKMP:(2746):Input = IKE_MESG_INTERNAL, IKE_PROCESS_COMPLETE
*Sep 10 08:56:02 UTC: ISAKMP:(2746):Old State = IKE_I_MM4 New State = IKE_I_MM5
*Sep 10 08:56:03 UTC: ISAKMP (2746): received packet from x.x.x.x dport 500 sport 500 Global (I) MM_KEY_EXCH
*Sep 10 08:56:03 UTC: ISAKMP:(2746): phase 1 packet is a duplicate of a previous packet.
*Sep 10 08:56:03 UTC: ISAKMP:(2746): retransmitting due to retransmit phase 1
*Sep 10 08:56:04 UTC: ISAKMP:(2746): retransmitting phase 1 MM_KEY_EXCH...
*Sep 10 08:56:04 UTC: ISAKMP (2746): incrementing error counter on sa, attempt 1 of 5: retransmit phase 1
*Sep 10 08:56:04 UTC: ISAKMP:(2746): retransmitting phase 1 MM_KEY_EXCH
*Sep 10 08:56:04 UTC: ISAKMP:(2746): sending packet to x.x.x.x my_port 4500 peer_port 4500 (I) MM_KEY_EXCH
*Sep 10 08:56:04 UTC: ISAKMP:(2746):Sending an IKE IPv4 Packet.