flannel/dist/ipsec

{
  "Network": "10.50.0.0/16",
  "Backend": {
    "Type": "ipsec",
    "PSK":"4bc1e570ff249cce3cc8cef5e2f8625bac76c7b02532f8bde9747196eb15a742480e265bbc0c60c265a8fe4eb6380cd1"
  }
}