Cisco ASA NAT Exemption

For your NAT, you’re saying this.

NAT the following:
NAT (INTERNAL IP) and change to (INTERNAL IP) in this case do not change it!
NAT (LAN2) and change to (LAN2) in this case do not change it!

NAT on ASA are broken the down like this every time.
Original Source IP:
Translated Source IP:
Destination IP:
Translated Destination IP:

If both source/destination stay the same, we are exempting them from all NAT statements, especially our PAT statement for internet traffic so they match our crypto ACL for a tunnel. This is called a NAT exemption for this reason.

You need to configure some variable within a tunnel group depending on the type. So you create it like you did with the tunnel-group NAME command. But you also need to clarify values.

As an example for a IPSec Remote Access Tunnel Group.
tunnel-group "tunnel_group_name" type ipsec-ra

For an IPSec RA tunnel for example, you need to configure some attributes.
tunnel-group "tunnel_group_name" general-attributes
In here you configure things like authentication servers, default group policy to reference.

For a L2L Tunnel group it might look something like this:

tunnel-group DefaultL2LGroup type ipsec-l2l
tunnel-group DefaultL2LGroup general-attributes
no accounting-server-group
default-group-policy DfltGrpPolicy
tunnel-group DefaultL2LGroup ipsec-attributes
no pre-shared-key
peer-id-validate req
no chain
no trust-point
isakmp keepalive threshold 10 retry 2
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