do-primary-remote-singlenet.sh

#!/bin/bash
# This script setups two clusters on a single network, that is, the
# two clusters work on same IP space, workload instances can reach
# each other directly without an Istio gateway. One cluster is
# considered primary, the other cluster is considered remote.

ColorOff='\033[0m'        # Text Reset
Black='\033[0;30m'        # Black
Red='\033[0;31m'          # Red
Green='\033[0;32m'        # Green


CLUSTER1_NAME=cluster1
CLUSTER2_NAME=cluster2
NAMESPACE=istio-system

if [[ $1 != '' ]]; then
  setupmcs -d
  exit 0
fi

LOADIMAGE=""
HUB="istio"
istioctlversion=$(istioctl version 2>/dev/null|head -1)
if [[ "${istioctlversion}" == *"-dev" ]]; then
  LOADIMAGE="-l"
  HUB="localhost:5000"
  if [[ -z "${TAG}" ]]; then
    TAG=$(docker images "localhost:5000/pilot:*" --format "{{.Tag}}")
  fi
fi
TAG="${TAG:-${istioctlversion}}"

echo ""
echo -e "Hub: ${Green}${HUB}${ColorOff}"
echo -e "Tag: ${Green}${TAG}${ColorOff}"
echo ""

# Use the script to setup a k8s cluster with Metallb installed and setup
cat <<EOF | setupmcs ${LOADIMAGE}
[
  {
    "kind": "Kubernetes",
    "clusterName": "${CLUSTER1_NAME}",
    "podSubnet": "10.10.0.0/16",
    "svcSubnet": "10.255.10.0/24",
    "network": "network1",
    "meta": {
      "kubeconfig": "/tmp/work/${CLUSTER1_NAME}"
    }
  },
  {
    "kind": "Kubernetes",
    "clusterName": "${CLUSTER2_NAME}",
    "podSubnet": "10.20.0.0/16",
    "svcSubnet": "10.255.20.0/24",
    "network": "network1",
    "meta": {
      "kubeconfig": "/tmp/work/${CLUSTER2_NAME}"
    }
  }
]
EOF


# Create the namespace for cluster1
kubectl create --context kind-${CLUSTER1_NAME} namespace ${NAMESPACE}
kubectl --context kind-${CLUSTER1_NAME} label namespace ${NAMESPACE} topology.istio.io/network=network1

# Setup the cacerts
./makecerts.sh -d
./makecerts.sh -c kind-${CLUSTER1_NAME} -s ${NAMESPACE} -n ${CLUSTER1_NAME}

# Create the namespace for cluster2
kubectl create --context kind-${CLUSTER2_NAME} namespace ${NAMESPACE}
kubectl --context kind-${CLUSTER2_NAME} label namespace ${NAMESPACE} topology.istio.io/network=network1
kubectl --context kind-${CLUSTER2_NAME} annotate namespace ${NAMESPACE} topology.istio.io/controlPlaneClusters=*

# Setup the cacerts
./makecerts.sh -c kind-${CLUSTER2_NAME} -s ${NAMESPACE} -n ${CLUSTER2_NAME}

# Install istio onto the first cluster
cat <<EOF | istioctl install --context="kind-${CLUSTER1_NAME}" -y -f -
apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
spec:
  values:
    global:
      hub: ${HUB}
      tag: ${TAG}
      meshID: mesh1
      multiCluster:
        clusterName: ${CLUSTER1_NAME}
      network: network1
  components:
    ingressGateways:
    - name: istio-ingressgateway
      label:
        istio: ingressgateway
        app: istio-ingressgateway
        topology.istio.io/network: network1
      enabled: true
      k8s:
        env:
        - name: ISTIO_META_ROUTER_MODE
          value: "sni-dnat"
        - name: ISTIO_META_REQUESTED_NETWORK_VIEW
          value: network1
        service:
          ports:
          - name: status-port
            port: 15021
            targetPort: 15021
          - name: tls
            port: 15443
            targetPort: 15443
          - name: https
            port: 443
            targetPort: 8443
          - name: tls-istiod
            port: 15012
            targetPort: 15012
          - name: tls-webhook
            port: 15017
            targetPort: 15017
    pilot:
      enabled: true
      k8s:
        env:
        - name: INJECTION_WEBHOOK_CONFIG_NAME
          value: "istio-sidecar-injector"
        - name: VALIDATION_WEBHOOK_CONFIG_NAME
          value: "istiod-default-validator"
        - name: EXTERNAL_ISTIOD
          value: "true"
EOF

# Expose the control plan
cat << EOF | kubectl apply --context="kind-${CLUSTER1_NAME}" -n ${NAMESPACE} -f -
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: istiod-gateway
spec:
  selector:
    istio: ingressgateway
  servers:
    - port:
        name: tls-istiod
        number: 15012
        protocol: tls
      tls:
        mode: PASSTHROUGH
      hosts:
        - "*"
    - port:
        name: tls-istiodwebhook
        number: 15017
        protocol: tls
      tls:
        mode: PASSTHROUGH
      hosts:
        - "*"
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: istiod-vs
spec:
  hosts:
  - "*"
  gateways:
  - istiod-gateway
  tls:
  - match:
    - port: 15012
      sniHosts:
      - "*"
    route:
    - destination:
        host: istiod.${NAMESPACE}.svc.cluster.local
        port:
          number: 15012
  - match:
    - port: 15017
      sniHosts:
      - "*"
    route:
    - destination:
        host: istiod.${NAMESPACE}.svc.cluster.local
        port:
          number: 443
EOF

# Get the ingress gateway IP address
while : ; do
  DISCOVERY_ADDRESS=$(kubectl --context="kind-${CLUSTER1_NAME}" get svc istio-ingressgateway \
       -n ${NAMESPACE} -o=jsonpath='{.status.loadBalancer.ingress[0].ip }')
  if [[ ! -z ${DISCOVERY_ADDRESS} ]]; then
    break
  fi
  echo -e ${Green}Waiting${ColorOff} for Ingress Gateway to be ready...
  sleep 3
done

# Install istio onto the second cluster
cat <<EOF | istioctl install --context="kind-${CLUSTER2_NAME}" -y -f -
apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
spec:
  profile: external
  values:
    global:
      hub: ${HUB}
      tag: ${TAG}
      remotePilotAddress: ${DISCOVERY_ADDRESS}
    istiodRemote:
      injectionPath: /inject/cluster/${CLUSTER2_NAME}/net/network1
EOF

function fixupIstiodServiceAndEndpoints(){
action="${1,,}"
if [[ "${action}" == "delete" ]]; then
   kubectl delete --context="kind-${CLUSTER2_NAME}" -n ${NAMESPACE} endpoints istiod
   kubectl delete --context="kind-${CLUSTER2_NAME}" -n ${NAMESPACE} services istiod
else
cat << EOF | kubectl apply --context="kind-${CLUSTER2_NAME}" -f -
apiVersion: v1
kind: Service
metadata:
  name: istiod
  namespace: ${NAMESPACE}
spec:
  type: ClusterIP
  clusterIP:
  ports:
  - port: 15012
    name: tcp-istiod
    protocol: TCP
  - port: 443
    targetPort: 15017
    name: tcp-webhook
    protocol: TCP
---
apiVersion: v1
kind: Endpoints
metadata:
  name: istiod
  namespace: ${NAMESPACE}
subsets:
- addresses:
  - ip: ${DISCOVERY_ADDRESS}
  ports:
  - port: 15012
    name: tcp-istiod
    protocol: TCP
  - port: 15017
    name: tcp-webhook
    protocol: TCP
EOF
fi
}

# Use version compare sort to figure out if we need fixes
verValue=$(echo -e "1.15\n${TAG,,}" | sort -V)
verValue=$(echo $verValue)
# The version is less than 1.15, need to fix up the services and endpoints
if [[ "${verValue}" != "1.15 ${TAG,,}" ]]; then
  fixupIstiodServiceAndEndpoints delete
  fixupIstiodServiceAndEndpoints apply
fi

# add the cluster2 credential to cluster1
istioctl x create-remote-secret --context="kind-${CLUSTER2_NAME}" \
    --name=${CLUSTER2_NAME} --namespace ${NAMESPACE} | \
    kubectl apply --context="kind-${CLUSTER1_NAME}" -f -

exit 0

# these steps are for verify traffic happens across the boundary of the two clusters.
# deploy helloworld and sleep onto cluster1 as v1 helloworld

ColorOff='\033[0m'        # Text Reset
Black='\033[0;30m'        # Black
Red='\033[0;31m'          # Red
Green='\033[0;32m'        # Green

CLUSTER1_NAME=cluster1
CLUSTER2_NAME=cluster2
WORKLOADNS=sample

export CTX_NS=${WORKLOADNS}
export CTX_CLUSTER=kind-${CLUSTER1_NAME}
verification/helloworld.sh v1

# deploy helloworld and sleep onto cluster2 as v2 helloworld
export CTX_CLUSTER=kind-${CLUSTER2_NAME}
verification/helloworld.sh v2

# verify the traffic
function verify() {
  CLUSTERNAME=$1
  # get sleep podname
  PODNAME=$(kubectl get pod --context="${CLUSTERNAME}" -n ${WORKLOADNS} -l \
    app=sleep -o jsonpath='{.items[0].metadata.name}')

  echo -e ${Green}Ready to hit the helloworld service from ${PODNAME} in ${CLUSTERNAME} ${ColorOff}
  x=1; while [ $x -le 5 ]; do
    kubectl exec --context="${CLUSTERNAME}" -n ${CTX_NS} -c sleep ${PODNAME} \
      -- curl -sS helloworld.${CTX_NS}.svc.cluster.local:5000/hello
    x=$(( $x + 1 ))
  done

  # show proxy config endpoints
  echo "Endpoints for sleep pod"
  istioctl --context="${CLUSTERNAME}" proxy-config endpoints ${PODNAME}.${CTX_NS}
}

verify kind-${CLUSTER1_NAME}
verify kind-${CLUSTER2_NAME}