The /etc/inet/ike/ikev2.preshared file contains the preshared keys that are used by the IKEv2 service. The file is owned by ikeuser and protected at 0600.
You must customize the default ikev2.preshared file when you configure a rule in the ike/ikev2.config file that requires preshared keys. Because IKEv2 uses these preshared keys to authenticate IKEv2 peers, this file must be valid before the in.ikev2d daemon reads any rules that require preshared keys.