GRE Tunnel with IPSEC

Here is a example configuration of a GRE tunnel encapsulated with IPSEC.



#Near Router:
!
crypto isakmp policy 10
 encr aes 256
 authentication pre-share
 group 2
!
crypto isakmp key 6 CRYPTO-Map-Sample address 192.168.1.2 #(Far side address)
!
crypto ipsec security-association lifetime seconds 86400
!
crypto ipsec transform-set CRYPTO-Map-Sample esp-aes 256 esp-md5-hmac
crypto ipsec df-bit clear
!
crypto map CRYPTO-Map-Sample  10 ipsec-isakmp
 set peer 192.168.1.2
 set transform-set CRYPTO-Map-Sample
 match address CRYPTO-Map-Sample
 qos pre-classify
!
interface Tunnel10
 description "GRE Tunnel"
 ip address 172.16.1.1 255.255.255.248
 tunnel source FastEthernet1/1
 tunnel destination 192.168.1.2
!
interface FastEthernet1/1
 ip address 192.168.1.1 255.255.255.248
 no keepalive
 crypto map CRYPTO-Map-Sample
!
ip access-list extended CRYPTO-Map-Sample #(all traffic will be in the tunnel)
 permit eigrp any any
 permit ip any any
 permit tcp any any
 permit udp any any
!
router eigrp 100
 network 172.16.1.0 0.0.0.7
 network 192.168.1.0 0.0.0.7
 no auto-summary

----------------------------------------------
#Far Router
!
crypto isakmp policy 10
 encr aes 256
 authentication pre-share
 group 2
!
crypto isakmp key 6 CRYPTO-Map-Sample address 192.168.1.1 #(Near side address)
!
crypto ipsec security-association lifetime seconds 86400
!
crypto ipsec transform-set CRYPTO-Map-Sample esp-aes 256 esp-md5-hmac
crypto ipsec df-bit clear
!
crypto map CRYPTO-Map-Sample10 ipsec-isakmp
 set peer 192.168.1.1
 set transform-set CRYPTO-Map-Sample
 match address CRYPTO-Map-Sample
 qos pre-classify
!
interface Tunnel10
 description "GRE Tunnel"
 ip address 172.16.1.2 255.255.255.248
 tunnel source FastEthernet1/1
 tunnel destination 192.168.1.1
!
interface FastEthernet1/1
 ip address 192.168.1.2 255.255.255.248
 no keepalive
 crypto map CRYPTO-Map-Sample
!
ip access-list extended CRYPTO-Map-Sample #(all traffic will be in the tunnel)
 permit eigrp any any
 permit ip any any
 permit tcp any any
 permit udp any any
!
router eigrp 100
 network 172.16.1.0 0.0.0.7
 network 192.168.1.0 0.0.0.7
 no auto-summary