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Cisco ASA 5500 Series Configuration Guide using the CLI
Chapter73 Configuring LAN-to-LAN IPsec VPNs
Defining a Tunnel Group
There are two default tunnel groups in the ASA: DefaultRAGroup, which is the default IPsec
remote-access tunnel group, and DefaultL2Lgroup, which is the default IPsec LAN-to-LAN tunnel
group. You can modify them but not delete them.
You can also create one or more new tunnel groups to suit your environment. The ASA uses these groups
to configure default tunnel parameters for remote access and LAN-to-LAN tunnel groups when there is
no specific tunnel group identified during tunnel negotiation.
To establish a basic LAN-to-LAN connection, you must set two attributes for a tunnel group:
•Set the connection type to IPsec LAN-to-LAN.
•Configure an authentication method for the IP, in the following example, preshared key for IKEv1
and IKEv2.
Note To use VPNs, including tunnel groups, the ASA must be in single-routed mode. The commands to
configure tunnel-group parameters do not appear in any other mode.
Step1 To set the connection type to IPsec LAN-to-LAN, enter the tunnel-group command. The syntax is
tunnel-group name type type, where name is the name you assign to the tunnel group, and type is the
type of tunnel. The tunnel types as you enter them in the CLI are:
•remote-access (IPsec, SSL, and clientless SSL remote access)
•ipsec-l2l (IPsec LAN to LAN)
In the following example the name of the tunnel group is the IP address of the LAN-to-LAN peer,
10.10.4.108.
hostname(config)# tunnel-group 10.10.4.108 type ipsec-l2l
hostname(config)#
Note LAN-to-LAN tunnel groups that have names that are not an IP address can be used only if the tunnel
authentication method is Digital Certificates and/or the peer is configured to use Aggressive Mode.
Step2 To set the authentication method to preshared key, enter the ipsec-attributes mode and then enter the
pre-shared-key command to create the preshared key. You need to use the same preshared key on both
ASAs for this LAN-to-LAN connection.
The key is an alphanumeric string of 1-128 characters.
In the following example the IKEv1 preshared key is 44kkaol59636jnfx:
hostname(config)# tunnel-group 10.10.4.108 ipsec-attributes
hostname(config-tunnel-ipsec)# pre-shared-key 44kkaol59636jnfx
In the next example, the IKEv2 preshared key is configured also as 44kkaol59636jnfx:
hostname(config-tunnel-ipsec)# ikev2 local-authentication pre-shared-key 44kkaol59636jnfx
Step3 Save your changes.
hostname(config)# write memory
hostname(config)#