Cisco IPSEC over GRE tunnel
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crypto isakmp policy 10
encr 3des
authentication pre-share
crypto isakmp key cisco1234 address 79.1.1.2
!
!
crypto ipsec transform-set VPN esp-aes
!
crypto map VPN 10 ipsec-isakmp
set peer 79.1.1.2
set transform-set VPN
match address 100
!
!
!
!
interface Loopback0
ip address 172.16.1.1 255.255.255.0
!
interface Tunnel0
ip address 10.72.1.1 255.255.255.252
tunnel source FastEthernet0/0
tunnel destination 79.1.1.2
!
interface Tunnel1
ip address 10.72.2.1 255.255.255.252
tunnel source FastEthernet1/0
tunnel destination 79.2.2.2
!
interface Tunnel2
ip address 10.72.3.1 255.255.255.252
tunnel source FastEthernet1/1
tunnel destination 79.3.3.2
!
interface Tunnel3
ip address 10.72.4.1 255.255.255.252
tunnel source FastEthernet2/0
tunnel destination 79.4.4.2
!
interface FastEthernet0/0
ip address 79.1.1.1 255.255.255.252
duplex half
crypto map VPN
!
interface FastEthernet1/0
ip address 79.2.2.1 255.255.255.252
duplex auto
speed auto
!
interface FastEthernet1/1
ip address 79.3.3.1 255.255.255.252
duplex auto
speed auto
!
interface FastEthernet2/0
ip address 79.4.4.1 255.255.255.252
duplex auto
speed auto
router ospf 1
log-adjacency-changes
network 10.72.1.0 0.0.0.3 area 0
network 10.72.2.0 0.0.0.3 area 0
network 10.72.3.0 0.0.0.3 area 0
network 10.72.4.0 0.0.0.3 area 0
network 172.16.1.0 0.0.0.255 area 0
access-list 100 permit gre any any
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crypto isakmp policy 10
encr 3des
authentication pre-share
crypto isakmp key cisco1234 address 79.1.1.1
!
!
crypto ipsec transform-set VPN esp-aes
!
crypto map VPN 10 ipsec-isakmp
set peer 79.1.1.1
set transform-set VPN
match address 100
interface Loopback0
ip address 172.16.3.1 255.255.255.0
!
interface Tunnel0
ip address 10.72.1.2 255.255.255.252
tunnel source FastEthernet0/0
tunnel destination 79.1.1.1
!
interface FastEthernet0/0
ip address 79.1.1.2 255.255.255.252
duplex half
crypto map VPN
access-list 100 permit gre any any