Refer to the exhibit. A new TAC engineer came to you for advice. A GRE over IPsec tunnel was configured, but the tunnel is not coming up.
What did the TAC engineer configure incorrectly?
A. The crypto map is not configured correctly.
B. The crypto ACL is not configured correctly.
C. The crypto map is not applied to the correct interface.
D. The OSPF network is not configured correctly.
Correct Answer: B
The access-list must also support GRE traffic with the “access-list 102 permit gre host 192.168.1.1 host
192.168.2.1” command -> B is correct.
Below is the correct configuration for GRE over IPsec on router B1 along with descriptions.