In IKEv2, which exchange establishes the first CHILD_SA?

Exhibit.

Refer to the exhibit, which contains a screenshot of some phase 1 settings.
The VPN is not up. To diagnose the issue, the administrator enters the following CLI commands on an SSH session on FortiGate:

However, the IKE real-time debug does not show any output. Why?

The local OSPF router is unable to establish adjacency with a peer.
Which two things should the administrator do to troubleshoot the issue? (Choose two.)

Refer to the exhibit, which shows the output of a BGP debug command.

What can you conclude about the router in this scenario?

Which three common FortiGate-to-collector-agent connectivity issues can you identify using the FSSO real-time debug? (Choose three.)