I have finally got this working, and yes, you can encapsulate ipsec inside
of a gre tunnel. Here is the details:
 
Isakmp actually happens outside of the tunnel, but the ESP packets are
indeed inside of the tunnel. I have verified this with wireshark, and esp is
encapsulated inside of the gre packets. The benefit if this would be to only
encrypt sensitive traffic while passing other traffic unencrypted inside of
a gre tunnel. Here is a partial config to setup the ipsec inside of gre:
 
crypto map map1 local-address fa0/1 
! this is required to setup isakmp outside of the tunnel
! ipsec sa's will not work if it tries to go through the gre tunnel
crypto map map1 10 ipsec-isakmp
 set peer 1.1.1.2
 ! make sure to set the peer as the physical interface and not the tunnel
interface
 ! otherwise ipsec sa's will fail to establish
 
cry
int fa0/1
 !outside interface
 ip address 1.1.1.1 255.255.255.0
int tun 0
 ip address 192.168.0.1 255.255.255.0
 tunnel source fa0/1
 tunnel destination 1.1.1.2
 crypto map map1
 
_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit 
www.ipexpert.com

Reply via email to