Fortigate IPSEC VPN with NAT to Cisco

Hi there,

I am trying to configure my fortigate 60b to IPSEC to a remote VPN site but has failed badly. The remote VPN is managed by an external vendor and the log provided by them shows

--------Cisco Log--------
%ASA-5-713075: Group =, IP =, Overriding Initiator's IPSec rekeying duration from 90000 to 28800 seconds
%ASA-6-602303: IPSEC: An outbound LAN-to-LAN SA (SPI= 0x3204778E) between and (user= has been created.
%ASA-5-713049: Group =, IP =, Security negotiation complete for LAN-to-LAN Group (  Responder, Inbound SPI = 0x282d31a3, Outbound SPI = 0x3204778e
%ASA-6-602303: IPSEC: An inbound LAN-to-LAN SA (SPI= 0x282D31A3) between and (user= has been created.
%ASA-5-713120: Group =, IP =, PHASE 2 COMPLETED (msgid=760d9eaf)
%ASA-4-402116: IPSEC: Received an ESP packet (SPI= 0x282D31A3, sequence number= 0x1) from (user= to  The decapsulated inner packet doesn't match the negotiated policy in the SA.  The packet specifies its destination as APP_SVR_A, its source as, and its protocol as 6.  The SA specifies its local proxy as and its remote_proxy as

The following is a brief desription = Local WAN interface = Remote VPN gateway = Remote network behind VPN gateway = Outgoing NAT IP
APP_SVR_A = Some remote server = client NAT IP

Basically I need to configure the Fortigate to establish IPSEC to remote Cisco device. The ACL over at remote site specifies that only client from can access the remote network. So NATing is required to NAT all outgoing traffic.

The following is the fortigate 60b config

---- start firewall config ----
set srcintf "internal"
set dstintf "wan1"
set srcaddr "Local Network"
set dstaddr "Remote Network"
set action ipsec
set schedule "always"
set service "ANY"
set natip
set inbound enable
set outbound enable
set natoutbound enable
set vpntunnel "VPN DR"
---- end firewall config ----

---- start phase1 ----
set interface "wan1"
set nattraversal enable
set dhgrp 2
set proposal 3des-sha1
set keylife 172800
set remote-gw
set psksecret ENC <somekey>
set keepalive 900
---- end phase1 ----      

---- start phase2 ----
set dhgrp 2
set keepalive enable
set pfs enable
set phase1name "VPN DR"
set proposal 3des-sha1
set replay enable
set dst-subnet
set keylifeseconds 90000
---- end phas2 ----

As the remote equipments are controlled by external party, the cisco vpn gateway configs were not available. Except the log that was provided.

Can any expert please explain what is meant by the Cisco log? particularly the last line. And how should i configure my fortigate to work with the remote cisco device?
Who is Participating?
rfc1180Connect With a Mentor Commented:
>does it mean that the SA is expecting to access instead of

their side is wrong, you can not NAT to the outside interface if it is the end point IP. They probably do not want you to use rfc1918 space, so if you have any available public space, you can use that instead.

rfc1180Connect With a Mentor Commented:
Tell the ASA side to change the ACL from to;

your config looks fine, the ASA Cisco log shows what is happening:

Phase 2 is completing, but there are no matching Proxy IDs
You are natting, so I am not sure what more they want, but really tell them to change the ACL to from

hayamiAuthor Commented:
unfortunately that is not going to happened because the vendor is incharged of the other side and they claimed that fortigate can be configured to meet their needs. unless based on the logs i can find that their ACL is wrong, else there is nothing i can do but to try to make it work.

i am particularly curious of this line

The SA specifies its local proxy as and its remote_proxy as

does it mean that the SA is expecting to access instead of
QlemoBatchelor and DeveloperCommented:
This question has been classified as abandoned and is being closed as part of the Cleanup Program.  See my comment at the end of the question for more details.
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