The main difference between new and legacy (pre-1.7) netpol semantics
are the following:
* The DenyDefault ingress isolation annotation is obsoleted.
* Traffic is allowed to a pod if there are no netpol selecting
the pod.
See https://kubernetes.io/docs/api-reference/v1.6/#networkpolicyspec-v1beta1-extensions
vs https://kubernetes.io/docs/api-reference/v1.7/#networkpolicyspec-v1-networking
for more details.
weave-npc can operate either in the legacy or the new mode (default). To
use the legacy, pass "--use-legacy-netpol" arg when starting the npc.
In non-legacy mode we create for each Namespace a default-allow ipset
which stores IP addrs of such Pods which are not selected by any
NetworkPolicy.The ipsets are dst's in rules of the WEAVE-NPC-DEFAULT chain.
Martynas Pumputis