Which two key configuration changes are needed on FortiGate to meet the design requirements?

A network administrator wants to set up redundant IPsec VPN tunnels on FortiGate by using two IPsec VPN tunnels and static routes.

* All traffic must be routed through the primary tunnel when both tunnels are up

* The secondary tunnel must be used only if the primary tunnel goes down

* In addition, FortiGate should be able to detect a dead tunnel to speed up tunnel failover

Which two key configuration changes are needed on FortiGate to meet the design requirements? (Choose two,)
A . Configure a high distance on the static route for the primary tunnel, and a lower distance on the static route for the secondary tunnel.
B. Enable Dead Peer Detection.
C. Configure a lower distance on the static route for the primary tunnel, and a higher distance on the static route for the secondary tunnel.
D. Enable Auto-negotiate and Autokey Keep Alive on the phase 2 configuration of both tunnels.

View Answer

Answer: B,C

Explanation:

Study Guide C IPsec VPN C IPsec configuration C Phase 1 Network.

When Dead Peer Detection (DPD) is enabled, DPD probes are sent to detect a failed tunnel and bring it down before its IPsec SAs expire. This failure detection mechanism is very useful when you have redundant paths to the same destination, and you want to failover to a backup connection when the primary connection fails to keep the connectivity between the sites up.

There are three DPD modes. On demand is the default mode.

Study Guide C IPsec VPN C Redundant VPNs.

Add one phase 1 configuration for each tunnel. DPD should be enabled on both ends.

Add at least one phase 2 definition for each phase 1.

Add one static route for each path. Use distance or priority to select primary routes over backup routes (routes for the primary VPN must have a lower distance or lower priority than the backup). Alternatively, use dynamic routing.

Configure FW policies for each IPsec interface.