IPSEC VPN with Loopback Interface


I have setup numerous IPSEC VPNS on my 1350 in the past but this particular one has me stumped, here is the IOS configuration:

Our WAN will be and please see below configured at our end. Once your side is configured the tunnel should come up. You will need to have a loopback configured at your end. Please use for tunnel interface IP.

interface Tunnel14
description VPN to Veripos Singapore
ip address
ip mtu 1420
ip flow ingress
ip tcp adjust-mss 1380
load-interval 30
keepalive 3 10
tunnel source
tunnel destination

crypto isakmp key XXXXXXXXX address

crypto map to_VPN 128 ipsec-isakmp
description GRE TO Veripos Singapore ]
set peer
set transform-set 3DES-SHA
match address GRE-TO-VER-SIN

ip route name Veripos_SIN_LoopBack
ip route Tunnel14 name Veripose_SIN_Data

ip access-list extended GRE-TO-VER-SIN
permit gre host host

Can you advise what I need to do to set this up especially the loopback part?



Hi Dave,

Can you share what you are trying to achieve? Based on the Cisco configuration above, you are trying to setup GRE instead of IPSec tunnel. I don’t see IPSec phase 1 proposal as well.

Can you share network diagram with IP addresses above also?


I am not too familiar with the remote end…here is the topolgy:



I guess my question really should be can I establish a GRE Tunnel from the 710? 6.1.2 build 3071

Hi Dave,

Thanks for the diagram. Below is my assumption, do correct me if I am wrong:-

  1. You need inter-access between subnet and subnet behind Cisco router.

  2. You need to build GRE tunnel between B710 and Cisco router. GRE is supported in v6.2 GA. You may test it on v6.2 RC.

  3. is Cisco router loop back interface (if you can get this info)?

  4. is Cisco router gateway (if you can get this info)?


I think all of the above is correct given the IOS configuration posted above

I also need a loopback address at my side and a tunnel interface IP:

How do we proceed?



We should connect to the Cisco via WAN address


I have installed the Firmware RC, How do I go about building the GRE tunnel please?



Hi Dave,

  1. Please go http://<Your device’s IP>/cgi-bin/MANGA/support.cgi and enable GRE.

  1. Configure GRE as below.

  1. Please ensure change tunnel destination <B710 WAN IP> in Cisco router.

Hope this help.