Contents

Introduction

Prerequisites

Requirements

Components Used

Conventions

Symptom

Cause / Problem Description

Conditions / Environment

Resolution

Related Information

Introduction

This document provides information on how to make dynamic L2L tunnels fall into different tunnel groups.

Prerequisites

Requirements

There are no specific requirements for this document.

Components Used

This document is not restricted to specific software and hardware versions.

Conventions

Refer to Cisco Technical Tips Conventions for more information on document conventions.

Symptom

In this document's example, the network administrator needs to create VPN policies where different remote VPN spokes connecting to a hub should connect to separate Tunnel-Groups so that different VPN policies can be applied to each remote connection.

Cause / Problem Description

In dynamic L2L tunnels, one side of the tunnel (the initiator) has a dynamic IP address. Because the receive does not know which IP addresses they are coming from, unlike static L2L tunnels, different peers automatically fall into the Default L2L Group. However, in some situations this is not acceptable and the user might need to assign a different group-policy or pre-shared key to each peer.

Conditions / Environment

Resolution

This can be accomplished in these two ways:

- Certificates

The tunnel-group lookup process on the ASA will land the connections based on a certificate field presented by the spokes.

no tunnel-group-map enable rules

tunnel-group-map enable ou

tunnel-group-map enable ike-id

tunnel-group-map enable peer-ip

tunnel-group-map default-group DefaultRAGroup

- PSKs and Aggressive Mode

Not all users will have a PKI infrastructure. However, the same can still be accomplished using an aggressive mode parameter as described here:

HUB

crypto ipsec transform-set myset esp-3des esp-sha-hmac

crypto ipsec security-association lifetime seconds 28800

crypto ipsec security-association lifetime kilobytes 4608000

crypto dynamic-map mydyn 10 set transform-set myset

crypto map mymap 65535 ipsec-isakmp dynamic mydyn

crypto map mymap interface outside

crypto isakmp enable outside

crypto isakmp policy 10

authentication pre-share

encryption 3des

hash sha

group 2

lifetime 86400

tunnel-group SPOKE1 type ipsec-l2l

tunnel-group SPOKE1 ipsec-attributes

pre-shared-key cisco123

tunnel-group SPOKE2 type ipsec-l2l

tunnel-group SPOKE2 ipsec-attributes

pre-shared-key cisco456

SPOKE1

access-list interesting extended permit ip

192.168.15.0 255.255.255.0 192.168.1.0 255.255.255.0

crypto ipsec transform-set myset esp-3des esp-sha-hmac

crypto ipsec security-association lifetime seconds 28800

crypto ipsec security-association lifetime kilobytes 4608000

crypto map mymap 10 match address interesting

crypto map mymap 10 set peer 10.198.16.141

crypto map mymap 10 set transform-set myset

crypto map mymap 10 set phase1-mode aggressive

crypto map mymap interface outside

crypto isakmp identity key-id SPOKE1

crypto isakmp enable outside

crypto isakmp policy 10

authentication pre-share

encryption 3des

hash sha

group 2

lifetime 86400

tunnel-group 10.198.16.141 type ipsec-l2l

tunnel-group 10.198.16.141 ipsec-attributes

pre-shared-key cisco123

SPOKE2

ip access-list extended interesting

permit ip 192.168.16.0 0.0.0.255 192.168.1.0 0.0.0.255

crypto isakmp policy 10

encr 3des

authentication pre-share

group 2

crypto isakmp peer address 10.198.16.141

set aggressive-mode password cisco456

set aggressive-mode client-endpoint fqdn SPOKE2

crypto ipsec transform-set myset esp-3des esp-sha-hmac

crypto map mymap 10 ipsec-isakmp

set peer 10.198.16.141

set transform-set myset

match address interesting

interface FastEthernet0/0

crypto map mymap

HUB VERIFICATION

Session Type: LAN-to-LAN Detailed

Connection   : SPOKE2

Index        : 59                     IP Addr      : 10.198.16.132

Protocol     : IKE IPsec

Encryption   : 3DES                   Hashing      : SHA1

Bytes Tx     : 400                    Bytes Rx     : 400

Login Time   : 23:45:00 UTC Thu Oct 27 2011

Duration     : 0h:00m:18s

IKE Tunnels: 1

IPsec Tunnels: 1

IKE:

Tunnel ID    : 59.1

UDP Src Port : 500                    UDP Dst Port : 500

IKE Neg Mode : Aggressive             Auth Mode    : preSharedKeys

Encryption   : 3DES                   Hashing      : SHA1

Rekey Int (T): 86400 Seconds          Rekey Left(T): 86381 Seconds

D/H Group    : 2

Filter Name  :

IPsec:

Tunnel ID    : 59.2

Local Addr   : 192.168.1.0/255.255.255.0/0/0

Remote Addr  : 192.168.16.0/255.255.255.0/0/0

Encryption   : 3DES                   Hashing      : SHA1

Encapsulation: Tunnel

Rekey Int (T): 3600 Seconds           Rekey Left(T): 3581 Seconds

Rekey Int (D): 4608000 K-Bytes        Rekey Left(D): 4608000 K-Bytes

Idle Time Out: 30 Minutes             Idle TO Left : 29 Minutes

Bytes Tx     : 400                    Bytes Rx     : 400

Pkts Tx      : 4                      Pkts Rx      : 4

NAC:

Reval Int (T): 0 Seconds              Reval Left(T): 0 Seconds

SQ Int (T)   : 0 Seconds              EoU Age(T)   : 21 Seconds

Hold Left (T): 0 Seconds              Posture Token:

Redirect URL :

Connection   : SPOKE1

Index        : 60                     IP Addr      : 10.198.16.142

Protocol     : IKE IPsec

Encryption   : 3DES                   Hashing      : SHA1

Bytes Tx     : 400                    Bytes Rx     : 400

Login Time   : 23:45:12 UTC Thu Oct 27 2011

Duration     : 0h:00m:08s

IKE Tunnels: 1

IPsec Tunnels: 1

IKE:

Tunnel ID    : 60.1

UDP Src Port : 500                    UDP Dst Port : 500

IKE Neg Mode : Aggressive             Auth Mode    : preSharedKeys

Encryption   : 3DES                   Hashing      : SHA1

Rekey Int (T): 86400 Seconds          Rekey Left(T): 86391 Seconds

D/H Group    : 2

Filter Name  :

IPsec:

Tunnel ID    : 60.2

Local Addr   : 192.168.1.0/255.255.255.0/0/0

Remote Addr  : 192.168.15.0/255.255.255.0/0/0

Encryption   : 3DES                   Hashing      : SHA1

Encapsulation: Tunnel

Rekey Int (T): 28800 Seconds          Rekey Left(T): 28791 Seconds

Rekey Int (D): 4608000 K-Bytes        Rekey Left(D): 4608000 K-Bytes

Idle Time Out: 30 Minutes             Idle TO Left : 29 Minutes

Bytes Tx     : 400                    Bytes Rx     : 400

Pkts Tx      : 4                      Pkts Rx      : 4

NAC:

Reval Int (T): 0 Seconds              Reval Left(T): 0 Seconds

SQ Int (T)   : 0 Seconds              EoU Age(T)   : 9 Seconds

Hold Left (T): 0 Seconds              Posture Token:

Redirect URL :

Related Information

- Technical Support & Documentation - Cisco Systems