Configure a Site 2 Site VPN on a ASA

In this article I will be showing you how to configure a Site 2 Site VPN on a ASA.
Also included within this example is a group-policy (named "Example_Policy") which we restrict access between the 2 endpoints to just tcp/80 traffic.

Please Note : This example presumes that you have already created the object groups for Local_LAN and Remote_LAN.
Access-Lists

Add the ACLs which we will need to NAT, the encryption domain and the group policy.

        access-list Example_Policy_ACL extended permit tcp object-group Local_LAN object-group Remote_LAN eq 80
        access-list Example_Policy_ACL extended deny ip any any
        access-list Example_VPN_ACL permit ip object-group Local_LAN object-group Remote_LAN

Group Policy
Create your group policy which will restrict traffic between hosts within your encryption domain.
        group-policy Example_Policy internal
        group-policy Example_Policy attributes
              vpn-filter value Example_Policy_ACL
              default-group-policy Example_Policy

NAT
Add your No NAT for traffic within the encryption domain
        nat (outside) 0 access-list Example_VPN_ACL
Tunnel Group
Create your tunnel group which will include your pre-shared key.
       tunnel-group [Peer IP] type ipsec-l2l
       tunnel-group [Peer IP] general-attributes
            default-group-policy Example_Policy
       tunnel-group [Peer IP] ipsec-attributes
            pre-shared-key [pre-share key] 

Phase 1
        crypto isakmp identity address
        crypto isakmp enable outside

        crypto isakmp policy 10
           authentication pre-share
           encryption [?]
           hash [?]
           group [?]
           lifetime [secs]

Phase 2
        crypto ipsec transform-set [transform set name] esp-3des esp-sha-hmac
        crypto map outside interface outside
        crypto map outside set transform-set [transform set]
        crypto map outside 20 match address Example_VPN_ACL
        crypto map outside 20 set peer [Peer IP]
        crypto map outside 20 set security-association lifetime seconds [secs]

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