Zone egress

The ZoneEgress proxy is used to isolate outgoing traffic to Services in other zones or external Services in the local zone.

Since the ZoneEgress proxy uses Server Name Indication (SNI) to route traffic, mTLS is required.

This proxy is not attached to any specific workloads, it’s bound to a specific zone. A zone egress can proxy traffic between all meshes, so you only need one deployment in each zone.

When a zone egress is present:

• In a multi-zone deployment, all requests sent from local data plane proxies to other zones will be directed through the local zone egress instance, which will then direct the traffic to the proper instance of the zone ingress.
• All requests that are sent from local data plane proxies to external Services available within the zone will be directed through the local zone egress instance.

The ZoneEgress proxy currently is an optional component. In the future it will become required for using external services.

The ZoneEgress entity includes the following parameters:

• type: Must be ZoneEgress.
• name: The name of the ZoneEgress instance, it must be unique for any given zone.
• networking: The networking parameters of the zone egress.
  • address: The address of the network interface that the zone egress is listening on.
  • port: The port that zone egress is listening on.
  • admin: The parameters related to the Envoy Admin API.
    • port: The port that the Envoy Admin API will listen to.
• zone: The zone that the zone egress belongs to. This is auto-generated on the Kong Mesh control plane.

kumactl generate zone-token --valid-for 720h --scope egress > $TOKEN_FILE

type: ZoneEgress
name: zoneegress-1
networking:
  address: 192.168.0.1
  port: 10002

kuma-dp run \
--proxy-type=egress \
--cp-address=https://$CP_IP_ADRESS:5678 \
--dataplane-token-file=$TOKEN_FILE \
--dataplane-file=$CONFIG_FILE

A ZoneEgress deployment can be scaled horizontally.

In addition to mTLS, there’s a configuration in the Mesh resource to route traffic through the ZoneEgress:

echo "apiVersion: kuma.io/v1alpha1
kind: Mesh
metadata:
  name: default
spec:
  routing:
    zoneEgress: true
  mtls: # mTLS is required to use ZoneEgress
    [...]" | kubectl apply -f -

cat <<EOF | kumactl apply -f -
type: Mesh
name: default
mtls: # mTLS is required to use ZoneEgress
  [...]
routing:
  zoneEgress: true
EOF

This configuration will force cross zone communication and external services to go through ZoneEgress. If enabled but no ZoneEgress is available the communication will fail.