_This is a WIP document describing changes to the upcoming kops 1.8 release_

# Significant changes

* flannel now has a `backend` property in the manifest, which can be either `udp` or `vxlan`.  `udp`
is not recommended, but will be the default value for existing clusters or clusters created via manifests.
`kops create cluster` with `--networking flannel` will use `vxlan`, `--networking flannel-vxlan`
or `--networking flannel-udp` can be specified to explicitly choose a backend mode.

# Required Actions

* Existing Calico users on clusters that were created prior to kops 1.8.0
  need to be updated for the new "DefaultDeny" behavior for Kubernetes NetworkPolicies.
  See the *Changes to k8s-policy* section in the
  [Calico release notes](https://github.com/projectcalico/calico/releases/tag/v2.4.0)
  for help.

# Full changelist

* ExperimentalCriticalPodAnnotation feature gate is now enabled by default in kubelet [@andreychernih](https://github.com/andreychernih) [#3345](https://github.com/kubernetes/kops/pull/3345)
* Upgrade Calico to v2.4.1 (thanks @tmjd)