istio
/
istio.io
mirror of https://github.com/istio/istio.io.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
istio.io/content/en/docs/setup/install/external-controlplane/index.md

917 lines
36 KiB
Markdown
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

---
title: Install Istio with an External Control Plane
description: Install Istio with an external control plane and a remote cluster data plane.
weight: 50
aliases:
- /docs/setup/additional-setup/external-controlplane/
- /latest/docs/setup/additional-setup/external-controlplane/
keywords: [external,control,istiod,remote]
owner: istio/wg-environments-maintainers
test: yes
---
This guide walks you through the process of installing an {{< gloss >}}external control plane{{< /gloss >}}
and then connecting one or more {{< gloss "remote cluster" >}}remote clusters{{< /gloss >}} to it.
The external control plane [deployment model](/docs/ops/deployment/deployment-models/#control-plane-models)
allows a mesh operator to install and manage a control plane on an external cluster, separate from the data
plane cluster (or multiple clusters) comprising the mesh. This deployment model allows a clear separation
between mesh operators and mesh administrators. Mesh operators install and manage Istio control planes while mesh
admins only need to configure the mesh.
{{< image width="75%"
link="external-controlplane.svg"
caption="External control plane cluster and remote cluster"
>}}
Envoy proxies (sidecars and gateways) running in the remote cluster access the external istiod via an ingress gateway
which exposes the endpoints needed for discovery, CA, injection, and validation.
While configuration and management of the external control plane is done by the mesh operator in the external cluster,
the first remote cluster connected to an external control plane serves as the config cluster for the mesh itself.
The mesh administrator will use the config cluster to configure the mesh resources (gateways, virtual services, etc.)
in addition to the mesh services themselves. The external control plane will remotely access this configuration from
the Kubernetes API server, as shown in the above diagram.
## Before you begin
### Clusters
This guide requires that you have two Kubernetes clusters with any of the
[supported Kubernetes versions:](/docs/releases/supported-releases#support-status-of-istio-releases) {{< supported_kubernetes_versions >}}.
The first cluster will host the {{< gloss >}}external control plane{{< /gloss >}} installed in the
`external-istiod` namespace. An ingress gateway is also installed in the `istio-system` namespace to provide
cross-cluster access to the external control plane.
The second cluster is a {{< gloss >}}remote cluster{{< /gloss >}} that will run the mesh application workloads.
Its Kubernetes API server also provides the mesh configuration used by the external control plane (istiod)
to configure the workload proxies.
### API server access
The Kubernetes API server in the remote cluster must be accessible to the external
control plane cluster. Many cloud providers make API servers publicly accessible
via network load balancers (NLBs). If the API server is not directly accessible, you will
need to modify the installation procedure to enable access. For example, the
[east-west](https://en.wikipedia.org/wiki/East-west_traffic) gateway used in a
[multicluster configuration](#adding-clusters) could also be used to enable access
to the API server.
### Environment Variables
The following environment variables will be used throughout to simplify the instructions:
Variable | Description
-------- | -----------
`CTX_EXTERNAL_CLUSTER` | The context name in the default [Kubernetes configuration file](https://kubernetes.io/docs/tasks/access-application-cluster/configure-access-multiple-clusters/) used for accessing the external control plane cluster.
`CTX_REMOTE_CLUSTER` | The context name in the default [Kubernetes configuration file](https://kubernetes.io/docs/tasks/access-application-cluster/configure-access-multiple-clusters/) used for accessing the remote cluster.
`REMOTE_CLUSTER_NAME` | The name of the remote cluster.
`EXTERNAL_ISTIOD_ADDR` | The hostname for the ingress gateway on the external control plane cluster. This is used by the remote cluster to access the external control plane.
`SSL_SECRET_NAME` | The name of the secret that holds the TLS certs for the ingress gateway on the external control plane cluster.
Set the `CTX_EXTERNAL_CLUSTER`, `CTX_REMOTE_CLUSTER`, and `REMOTE_CLUSTER_NAME` now. You will set the others later.
{{< text syntax=bash snip_id=none >}}
$ export CTX_EXTERNAL_CLUSTER=<your external cluster context>
$ export CTX_REMOTE_CLUSTER=<your remote cluster context>
$ export REMOTE_CLUSTER_NAME=<your remote cluster name>
{{< /text >}}
## Cluster configuration
### Mesh operator steps
A mesh operator is responsible for installing and managing the external Istio control plane on the external cluster.
This includes configuring an ingress gateway on the external cluster, which allows the remote cluster to access the control plane,
and installing the sidecar injector webhook configuration on the remote cluster so that it will use the external control plane.
#### Set up a gateway in the external cluster
1. Create the Istio install configuration for the ingress gateway that will expose the external control plane ports to other clusters:
{{< text bash >}}
$ cat <<EOF > controlplane-gateway.yaml
apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
metadata:
namespace: istio-system
spec:
components:
ingressGateways:
- name: istio-ingressgateway
enabled: true
k8s:
service:
ports:
- port: 15021
targetPort: 15021
name: status-port
- port: 15012
targetPort: 15012
name: tls-xds
- port: 15017
targetPort: 15017
name: tls-webhook
EOF
{{< /text >}}
Then, install the gateway in the `istio-system` namespace of the external cluster:
{{< text bash >}}
$ istioctl install -f controlplane-gateway.yaml --context="${CTX_EXTERNAL_CLUSTER}"
{{< /text >}}
1. Run the following command to confirm that the ingress gateway is up and running:
{{< text bash >}}
$ kubectl get po -n istio-system --context="${CTX_EXTERNAL_CLUSTER}"
NAME READY STATUS RESTARTS AGE
istio-ingressgateway-9d4c7f5c7-7qpzz 1/1 Running 0 29s
istiod-68488cd797-mq8dn 1/1 Running 0 38s
{{< /text >}}
You will notice an istiod deployment is also created in the `istio-system` namespace. This is used to configure the ingress gateway
and is NOT the control plane used by remote clusters.
{{< tip >}}
This ingress gateway could be configured to host multiple external control planes, in different namespaces on the external cluster,
although in this example you will only deploy a single external istiod in the `external-istiod` namespace.
{{< /tip >}}
1. Configure your environment to expose the Istio ingress gateway service using a public hostname with TLS.
Set the `EXTERNAL_ISTIOD_ADDR` environment variable to the hostname and `SSL_SECRET_NAME` environment variable to the secret that holds the TLS certs:
{{< text syntax=bash snip_id=none >}}
$ export EXTERNAL_ISTIOD_ADDR=<your external istiod host>
$ export SSL_SECRET_NAME=<your external istiod secret>
{{< /text >}}
These instructions assume that you are exposing the external cluster's gateway using a hostname with properly signed DNS certs
as this is the recommended approach in a production environment.
Refer to the [secure ingress task](/docs/tasks/traffic-management/ingress/secure-ingress/#configure-a-tls-ingress-gateway-for-a-single-host)
for more information on exposing a secure gateway.
Your environment variables should look something like this:
{{< text bash >}}
$ echo "$EXTERNAL_ISTIOD_ADDR" "$SSL_SECRET_NAME"
myhost.example.com myhost-example-credential
{{< /text >}}
{{< tip >}}
If you don't have a DNS hostname but want to experiment with an external control plane in a test environment,
you can access the gateway using its external load balancer IP address:
{{< text bash >}}
$ export EXTERNAL_ISTIOD_ADDR=$(kubectl -n istio-system --context="${CTX_EXTERNAL_CLUSTER}" get svc istio-ingressgateway -o jsonpath='{.status.loadBalancer.ingress[0].ip}')
$ export SSL_SECRET_NAME=NONE
{{< /text >}}
Doing this will also require a few other changes in the configuration. Make sure to follow all of the related steps
in the instructions below.
{{< /tip >}}
#### Set up the remote config cluster
1. Use the `remote` profile to configure the remote cluster's Istio installation. This installs an injection
webhook that uses the external control plane's injector, instead of a locally deployed one. Because this cluster
will also serve as the config cluster, the Istio CRDs and other resources that will be needed on the remote cluster
are also installed by setting `global.configCluster` and `pilot.configMap` to `true`:
{{< text syntax=bash snip_id=get_remote_config_cluster_iop >}}
$ cat <<EOF > remote-config-cluster.yaml
apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
metadata:
namespace: external-istiod
spec:
profile: remote
values:
global:
istioNamespace: external-istiod
configCluster: true
pilot:
configMap: true
istiodRemote:
injectionURL: https://${EXTERNAL_ISTIOD_ADDR}:15017/inject/cluster/${REMOTE_CLUSTER_NAME}/net/network1
base:
validationURL: https://${EXTERNAL_ISTIOD_ADDR}:15017/validate
EOF
{{< /text >}}
{{< tip >}}
If your cluster name contains `/` (slash) characters, replace them with `--slash--` in the `injectionURL`,
e.g., `injectionURL: https://1.2.3.4:15017/inject/cluster/`<mark>`cluster--slash--1`</mark>`/net/network1`.
{{< /tip >}}
1. If you are using an IP address for the `EXTERNAL_ISTIOD_ADDR`, instead of a proper DNS hostname,
modify the configuration to specify the discovery address and paths, instead of URLs:
{{< warning >}}
This is not recommended in a production environment.
{{< /warning >}}
{{< text bash >}}
$ sed -i'.bk' \
-e "s|injectionURL: https://${EXTERNAL_ISTIOD_ADDR}:15017|injectionPath: |" \
-e "/istioNamespace:/a\\
remotePilotAddress: ${EXTERNAL_ISTIOD_ADDR}" \
-e '/base:/,+1d' \
remote-config-cluster.yaml; rm remote-config-cluster.yaml.bk
{{< /text >}}
1. Install the configuration on the remote cluster:
{{< text bash >}}
$ kubectl create namespace external-istiod --context="${CTX_REMOTE_CLUSTER}"
$ istioctl manifest generate -f remote-config-cluster.yaml --set values.defaultRevision=default | kubectl apply --context="${CTX_REMOTE_CLUSTER}" -f -
{{< /text >}}
1. Confirm that the remote cluster's injection webhook configuration has been installed:
{{< text bash >}}
$ kubectl get mutatingwebhookconfiguration --context="${CTX_REMOTE_CLUSTER}"
NAME WEBHOOKS AGE
istio-sidecar-injector-external-istiod 4 6m24s
{{< /text >}}
1. Confirm that the remote cluster's validation webhook configurations have been installed:
{{< text bash >}}
$ kubectl get validatingwebhookconfiguration --context="${CTX_REMOTE_CLUSTER}"
NAME WEBHOOKS AGE
istio-validator-external-istiod 1 6m53s
istiod-default-validator 1 6m53s
{{< /text >}}
#### Set up the control plane in the external cluster
1. Create the `external-istiod` namespace, which will be used to host the external control plane:
{{< text bash >}}
$ kubectl create namespace external-istiod --context="${CTX_EXTERNAL_CLUSTER}"
{{< /text >}}
1. The control plane in the external cluster needs access to the remote cluster to discover services, endpoints,
and pod attributes. Create a secret with credentials to access the remote cluster’s `kube-apiserver` and install
it in the external cluster:
{{< text bash >}}
$ kubectl create sa istiod-service-account -n external-istiod --context="${CTX_EXTERNAL_CLUSTER}"
$ istioctl create-remote-secret \
--context="${CTX_REMOTE_CLUSTER}" \
--type=config \
--namespace=external-istiod \
--service-account=istiod \
--create-service-account=false | \
kubectl apply -f - --context="${CTX_EXTERNAL_CLUSTER}"
{{< /text >}}
1. Create the Istio configuration to install the control plane in the `external-istiod` namespace of the external cluster.
Notice that istiod is configured to use the locally mounted `istio` configmap and the `SHARED_MESH_CONFIG` environment
variable is set to `istio`. This instructs istiod to merge the values set by the mesh admin in the config cluster's
configmap with the values in the local configmap set by the mesh operator, here, which will take precedence
if there are any conflicts:
{{< text syntax=bash snip_id=get_external_istiod_iop >}}
$ cat <<EOF > external-istiod.yaml
apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
metadata:
namespace: external-istiod
spec:
profile: empty
meshConfig:
rootNamespace: external-istiod
defaultConfig:
discoveryAddress: $EXTERNAL_ISTIOD_ADDR:15012
proxyMetadata:
XDS_ROOT_CA: /etc/ssl/certs/ca-certificates.crt
CA_ROOT_CA: /etc/ssl/certs/ca-certificates.crt
components:
pilot:
enabled: true
k8s:
overlays:
- kind: Deployment
name: istiod
patches:
- path: spec.template.spec.volumes[100]
value: |-
name: config-volume
configMap:
name: istio
- path: spec.template.spec.volumes[100]
value: |-
name: inject-volume
configMap:
name: istio-sidecar-injector
- path: spec.template.spec.containers[0].volumeMounts[100]
value: |-
name: config-volume
mountPath: /etc/istio/config
- path: spec.template.spec.containers[0].volumeMounts[100]
value: |-
name: inject-volume
mountPath: /var/lib/istio/inject
env:
- name: INJECTION_WEBHOOK_CONFIG_NAME
value: ""
- name: VALIDATION_WEBHOOK_CONFIG_NAME
value: ""
- name: EXTERNAL_ISTIOD
value: "true"
- name: LOCAL_CLUSTER_SECRET_WATCHER
value: "true"
- name: CLUSTER_ID
value: ${REMOTE_CLUSTER_NAME}
- name: SHARED_MESH_CONFIG
value: istio
values:
global:
caAddress: $EXTERNAL_ISTIOD_ADDR:15012
istioNamespace: external-istiod
operatorManageWebhooks: true
configValidation: false
meshID: mesh1
multiCluster:
clusterName: ${REMOTE_CLUSTER_NAME}
network: network1
EOF
{{< /text >}}
1. If you are using an IP address for the `EXTERNAL_ISTIOD_ADDR`, instead of a proper DNS hostname,
delete the proxy metadata and update the webhook config environment variables in the configuration:
{{< warning >}}
This is not recommended in a production environment.
{{< /warning >}}
{{< text bash >}}
$ sed -i'.bk' \
-e '/proxyMetadata:/,+2d' \
-e '/INJECTION_WEBHOOK_CONFIG_NAME/{n;s/value: ""/value: istio-sidecar-injector-external-istiod/;}' \
-e '/VALIDATION_WEBHOOK_CONFIG_NAME/{n;s/value: ""/value: istio-validator-external-istiod/;}' \
external-istiod.yaml ; rm external-istiod.yaml.bk
{{< /text >}}
1. Apply the Istio configuration on the external cluster:
{{< text bash >}}
$ istioctl install -f external-istiod.yaml --context="${CTX_EXTERNAL_CLUSTER}"
{{< /text >}}
1. Confirm that the external istiod has been successfully deployed:
{{< text bash >}}
$ kubectl get po -n external-istiod --context="${CTX_EXTERNAL_CLUSTER}"
NAME READY STATUS RESTARTS AGE
istiod-779bd6fdcf-bd6rg 1/1 Running 0 70s
{{< /text >}}
1. Create the Istio `Gateway`, `VirtualService`, and `DestinationRule` configuration to route traffic from the ingress
gateway to the external control plane:
{{< text syntax=bash snip_id=get_external_istiod_gateway_config >}}
$ cat <<EOF > external-istiod-gw.yaml
apiVersion: networking.istio.io/v1
kind: Gateway
metadata:
name: external-istiod-gw
namespace: external-istiod
spec:
selector:
istio: ingressgateway
servers:
- port:
number: 15012
protocol: https
name: https-XDS
tls:
mode: SIMPLE
credentialName: $SSL_SECRET_NAME
hosts:
- $EXTERNAL_ISTIOD_ADDR
- port:
number: 15017
protocol: https
name: https-WEBHOOK
tls:
mode: SIMPLE
credentialName: $SSL_SECRET_NAME
hosts:
- $EXTERNAL_ISTIOD_ADDR
---
apiVersion: networking.istio.io/v1
kind: VirtualService
metadata:
name: external-istiod-vs
namespace: external-istiod
spec:
hosts:
- $EXTERNAL_ISTIOD_ADDR
gateways:
- external-istiod-gw
http:
- match:
- port: 15012
route:
- destination:
host: istiod.external-istiod.svc.cluster.local
port:
number: 15012
- match:
- port: 15017
route:
- destination:
host: istiod.external-istiod.svc.cluster.local
port:
number: 443
---
apiVersion: networking.istio.io/v1
kind: DestinationRule
metadata:
name: external-istiod-dr
namespace: external-istiod
spec:
host: istiod.external-istiod.svc.cluster.local
trafficPolicy:
portLevelSettings:
- port:
number: 15012
tls:
mode: SIMPLE
connectionPool:
http:
h2UpgradePolicy: UPGRADE
- port:
number: 443
tls:
mode: SIMPLE
EOF
{{< /text >}}
1. If you are using an IP address for the `EXTERNAL_ISTIOD_ADDR`, instead of a proper DNS hostname,
modify the configuration.
Delete the `DestinationRule`, don't terminate TLS in the `Gateway`, and use TLS routing in the `VirtualService`:
{{< warning >}}
This is not recommended in a production environment.
{{< /warning >}}
{{< text bash >}}
$ sed -i'.bk' \
-e '55,$d' \
-e 's/mode: SIMPLE/mode: PASSTHROUGH/' -e '/credentialName:/d' -e "s/${EXTERNAL_ISTIOD_ADDR}/\"*\"/" \
-e 's/http:/tls:/' -e 's/https/tls/' -e '/route:/i\
sniHosts:\
- "*"' \
external-istiod-gw.yaml; rm external-istiod-gw.yaml.bk
{{< /text >}}
1. Apply the configuration on the external cluster:
{{< text bash >}}
$ kubectl apply -f external-istiod-gw.yaml --context="${CTX_EXTERNAL_CLUSTER}"
{{< /text >}}
### Mesh admin steps
Now that Istio is up and running, a mesh administrator only needs to deploy and configure services in the mesh,
including gateways, if needed.
{{< tip >}}
Some of the `istioctl` CLI commands won't work by default on a remote cluster,
although you can easily configure `istioctl` to make it fully functional.
See the [Istioctl-proxy Ecosystem project](https://github.com/istio-ecosystem/istioctl-proxy-sample) for details.
{{< /tip >}}
#### Deploy a sample application
1. Create, and label for injection, the `sample` namespace on the remote cluster:
{{< text bash >}}
$ kubectl create --context="${CTX_REMOTE_CLUSTER}" namespace sample
$ kubectl label --context="${CTX_REMOTE_CLUSTER}" namespace sample istio-injection=enabled
{{< /text >}}
1. Deploy the `helloworld` (`v1`) and `sleep` samples:
{{< text bash >}}
$ kubectl apply -f @samples/helloworld/helloworld.yaml@ -l service=helloworld -n sample --context="${CTX_REMOTE_CLUSTER}"
$ kubectl apply -f @samples/helloworld/helloworld.yaml@ -l version=v1 -n sample --context="${CTX_REMOTE_CLUSTER}"
$ kubectl apply -f @samples/sleep/sleep.yaml@ -n sample --context="${CTX_REMOTE_CLUSTER}"
{{< /text >}}
1. Wait a few seconds for the `helloworld` and `sleep` pods to be running with sidecars injected:
{{< text bash >}}
$ kubectl get pod -n sample --context="${CTX_REMOTE_CLUSTER}"
NAME READY STATUS RESTARTS AGE
helloworld-v1-776f57d5f6-s7zfc 2/2 Running 0 10s
sleep-64d7d56698-wqjnm 2/2 Running 0 9s
{{< /text >}}
1. Send a request from the `sleep` pod to the `helloworld` service:
{{< text bash >}}
$ kubectl exec --context="${CTX_REMOTE_CLUSTER}" -n sample -c sleep \
"$(kubectl get pod --context="${CTX_REMOTE_CLUSTER}" -n sample -l app=sleep -o jsonpath='{.items[0].metadata.name}')" \
-- curl -sS helloworld.sample:5000/hello
Hello version: v1, instance: helloworld-v1-776f57d5f6-s7zfc
{{< /text >}}
#### Enable gateways
{{< tip >}}
{{< boilerplate gateway-api-future >}}
If you use the Gateway API, you will not need to install any gateway components. You can
skip the following instructions and proceed directly to [configure and test an ingress gateway](#configure-and-test-an-ingress-gateway).
{{< /tip >}}
Enable an ingress gateway on the remote cluster:
{{< tabset category-name="ingress-gateway-install-type" >}}
{{< tab name="IstioOperator" category-value="iop" >}}
{{< text bash >}}
$ cat <<EOF > istio-ingressgateway.yaml
apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
spec:
profile: empty
components:
ingressGateways:
- namespace: external-istiod
name: istio-ingressgateway
enabled: true
values:
gateways:
istio-ingressgateway:
injectionTemplate: gateway
EOF
$ istioctl install -f istio-ingressgateway.yaml --set values.global.istioNamespace=external-istiod --context="${CTX_REMOTE_CLUSTER}"
{{< /text >}}
{{< /tab >}}
{{< tab name="Helm" category-value="helm" >}}
{{< text bash >}}
$ helm install istio-ingressgateway istio/gateway -n external-istiod --kube-context="${CTX_REMOTE_CLUSTER}"
{{< /text >}}
See [Installing Gateways](/docs/setup/additional-setup/gateway/) for in-depth documentation on gateway installation.
{{< /tab >}}
{{< /tabset >}}
You can optionally enable other gateways as well. For example, an egress gateway:
{{< tabset category-name="egress-gateway-install-type" >}}
{{< tab name="IstioOperator" category-value="iop" >}}
{{< text bash >}}
$ cat <<EOF > istio-egressgateway.yaml
apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
spec:
profile: empty
components:
egressGateways:
- namespace: external-istiod
name: istio-egressgateway
enabled: true
values:
gateways:
istio-egressgateway:
injectionTemplate: gateway
EOF
$ istioctl install -f istio-egressgateway.yaml --set values.global.istioNamespace=external-istiod --context="${CTX_REMOTE_CLUSTER}"
{{< /text >}}
{{< /tab >}}
{{< tab name="Helm" category-value="helm" >}}
{{< text bash >}}
$ helm install istio-egressgateway istio/gateway -n external-istiod --kube-context="${CTX_REMOTE_CLUSTER}" --set service.type=ClusterIP
{{< /text >}}
See [Installing Gateways](/docs/setup/additional-setup/gateway/) for in-depth documentation on gateway installation.
{{< /tab >}}
{{< /tabset >}}
#### Configure and test an ingress gateway
{{< tip >}}
{{< boilerplate gateway-api-choose >}}
{{< /tip >}}
1. Make sure that the cluster is ready to configure the gateway:
{{< tabset category-name="config-api" >}}
{{< tab name="Istio APIs" category-value="istio-apis" >}}
Confirm that the Istio ingress gateway is running:
{{< text bash >}}
$ kubectl get pod -l app=istio-ingressgateway -n external-istiod --context="${CTX_REMOTE_CLUSTER}"
NAME READY STATUS RESTARTS AGE
istio-ingressgateway-7bcd5c6bbd-kmtl4 1/1 Running 0 8m4s
{{< /text >}}
{{< /tab >}}
{{< tab name="Gateway API" category-value="gateway-api" >}}
The Kubernetes Gateway API CRDs do not come installed by default on most Kubernetes clusters, so make sure they are
installed before using the Gateway API:
{{< text syntax=bash snip_id=install_crds >}}
$ kubectl get crd gateways.gateway.networking.k8s.io --context="${CTX_REMOTE_CLUSTER}" &> /dev/null || \
{ kubectl kustomize "github.com/kubernetes-sigs/gateway-api/config/crd?ref={{< k8s_gateway_api_version >}}" | kubectl apply -f - --context="${CTX_REMOTE_CLUSTER}"; }
{{< /text >}}
{{< /tab >}}
{{< /tabset >}}
2) Expose the `helloworld` application on an ingress gateway:
{{< tabset category-name="config-api" >}}
{{< tab name="Istio APIs" category-value="istio-apis" >}}
{{< text bash >}}
$ kubectl apply -f @samples/helloworld/helloworld-gateway.yaml@ -n sample --context="${CTX_REMOTE_CLUSTER}"
{{< /text >}}
{{< /tab >}}
{{< tab name="Gateway API" category-value="gateway-api" >}}
{{< text bash >}}
$ kubectl apply -f @samples/helloworld/gateway-api/helloworld-gateway.yaml@ -n sample --context="${CTX_REMOTE_CLUSTER}"
{{< /text >}}
{{< /tab >}}
{{< /tabset >}}
3) Set the `GATEWAY_URL` environment variable
(see [determining the ingress IP and ports](/docs/tasks/traffic-management/ingress/ingress-control/#determining-the-ingress-ip-and-ports) for details):
{{< tabset category-name="config-api" >}}
{{< tab name="Istio APIs" category-value="istio-apis" >}}
{{< text bash >}}
$ export INGRESS_HOST=$(kubectl -n external-istiod --context="${CTX_REMOTE_CLUSTER}" get service istio-ingressgateway -o jsonpath='{.status.loadBalancer.ingress[0].ip}')
$ export INGRESS_PORT=$(kubectl -n external-istiod --context="${CTX_REMOTE_CLUSTER}" get service istio-ingressgateway -o jsonpath='{.spec.ports[?(@.name=="http2")].port}')
$ export GATEWAY_URL=$INGRESS_HOST:$INGRESS_PORT
{{< /text >}}
{{< /tab >}}
{{< tab name="Gateway API" category-value="gateway-api" >}}
{{< text bash >}}
$ kubectl -n sample --context="${CTX_REMOTE_CLUSTER}" wait --for=condition=programmed gtw helloworld-gateway
$ export INGRESS_HOST=$(kubectl -n sample --context="${CTX_REMOTE_CLUSTER}" get gtw helloworld-gateway -o jsonpath='{.status.addresses[0].value}')
$ export GATEWAY_URL=$INGRESS_HOST:80
{{< /text >}}
{{< /tab >}}
{{< /tabset >}}
4) Confirm you can access the `helloworld` application through the ingress gateway:
{{< text bash >}}
$ curl -s "http://${GATEWAY_URL}/hello"
Hello version: v1, instance: helloworld-v1-776f57d5f6-s7zfc
{{< /text >}}
## Adding clusters to the mesh (optional) {#adding-clusters}
This section shows you how to expand an existing external control plane mesh to multicluster by adding another remote cluster.
This allows you to easily distribute services and use [location-aware routing and fail over](/docs/tasks/traffic-management/locality-load-balancing/) to support high availability of your application.
{{< image width="75%"
link="external-multicluster.svg"
caption="External control plane with multiple remote clusters"
>}}
Unlike the first remote cluster, the second and subsequent clusters added to the same external control plane do not
provide mesh config, but instead are only sources of endpoint configuration, just like remote clusters in a
[primary-remote](/docs/setup/install/multicluster/primary-remote_multi-network/) Istio multicluster configuration.
To proceed, you'll need another Kubernetes cluster for the second remote cluster of the mesh. Set the following
environment variables to the context name and cluster name of the cluster:
{{< text syntax=bash snip_id=none >}}
$ export CTX_SECOND_CLUSTER=<your second remote cluster context>
$ export SECOND_CLUSTER_NAME=<your second remote cluster name>
{{< /text >}}
### Register the new cluster
1. Create the remote Istio install configuration, which installs the injection webhook that uses the
external control plane's injector, instead of a locally deployed one:
{{< text syntax=bash snip_id=get_second_remote_cluster_iop >}}
$ cat <<EOF > second-remote-cluster.yaml
apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
metadata:
namespace: external-istiod
spec:
profile: remote
values:
global:
istioNamespace: external-istiod
istiodRemote:
injectionURL: https://${EXTERNAL_ISTIOD_ADDR}:15017/inject/cluster/${SECOND_CLUSTER_NAME}/net/network2
EOF
{{< /text >}}
1. If you are using an IP address for the `EXTERNAL_ISTIOD_ADDR`, instead of a proper DNS hostname,
modify the configuration to specify the discovery address and path, instead of an injection URL:
{{< warning >}}
This is not recommended in a production environment.
{{< /warning >}}
{{< text bash >}}
$ sed -i'.bk' \
-e "s|injectionURL: https://${EXTERNAL_ISTIOD_ADDR}:15017|injectionPath: |" \
-e "/istioNamespace:/a\\
remotePilotAddress: ${EXTERNAL_ISTIOD_ADDR}" \
second-remote-cluster.yaml; rm second-remote-cluster.yaml.bk
{{< /text >}}
1. Create and annotate the system namespace on the remote cluster:
{{< text bash >}}
$ kubectl create namespace external-istiod --context="${CTX_SECOND_CLUSTER}"
$ kubectl annotate namespace external-istiod "topology.istio.io/controlPlaneClusters=${REMOTE_CLUSTER_NAME}" --context="${CTX_SECOND_CLUSTER}"
{{< /text >}}
The `topology.istio.io/controlPlaneClusters` annotation specifies the cluster ID of the external control plane that
should manage this remote cluster. Notice that this is the name of the first remote (config) cluster, which was used
to set the cluster ID of the external control plane when it was installed in the external cluster earlier.
1. Install the configuration on the remote cluster:
{{< text bash >}}
$ istioctl manifest generate -f second-remote-cluster.yaml | kubectl apply --context="${CTX_SECOND_CLUSTER}" -f -
{{< /text >}}
1. Confirm that the remote cluster's injection webhook configuration has been installed:
{{< text bash >}}
$ kubectl get mutatingwebhookconfiguration --context="${CTX_SECOND_CLUSTER}"
NAME WEBHOOKS AGE
istio-sidecar-injector-external-istiod 4 4m13s
{{< /text >}}
1. Create a secret with credentials to allow the control plane to access the endpoints on the second remote cluster
and install it:
{{< text bash >}}
$ istioctl create-remote-secret \
--context="${CTX_SECOND_CLUSTER}" \
--name="${SECOND_CLUSTER_NAME}" \
--type=remote \
--namespace=external-istiod \
--create-service-account=false | \
kubectl apply -f - --context="${CTX_EXTERNAL_CLUSTER}"
{{< /text >}}
Note that unlike the first remote cluster of the mesh, which also serves as the config cluster, the `--type` argument
is set to `remote` this time, instead of `config`.
### Setup east-west gateways
1. Deploy east-west gateways on both remote clusters:
{{< text bash >}}
$ @samples/multicluster/gen-eastwest-gateway.sh@ \
--network network1 > eastwest-gateway-1.yaml
$ istioctl manifest generate -f eastwest-gateway-1.yaml \
--set values.global.istioNamespace=external-istiod | \
kubectl apply --context="${CTX_REMOTE_CLUSTER}" -f -
{{< /text >}}
{{< text bash >}}
$ @samples/multicluster/gen-eastwest-gateway.sh@ \
--network network2 > eastwest-gateway-2.yaml
$ istioctl manifest generate -f eastwest-gateway-2.yaml \
--set values.global.istioNamespace=external-istiod | \
kubectl apply --context="${CTX_SECOND_CLUSTER}" -f -
{{< /text >}}
1. Wait for the east-west gateways to be assigned external IP addresses:
{{< text bash >}}
$ kubectl --context="${CTX_REMOTE_CLUSTER}" get svc istio-eastwestgateway -n external-istiod
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
istio-eastwestgateway LoadBalancer 10.0.12.121 34.122.91.98 ... 51s
{{< /text >}}
{{< text bash >}}
$ kubectl --context="${CTX_SECOND_CLUSTER}" get svc istio-eastwestgateway -n external-istiod
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
istio-eastwestgateway LoadBalancer 10.0.12.121 34.122.91.99 ... 51s
{{< /text >}}
1. Expose services via the east-west gateways:
{{< text bash >}}
$ kubectl --context="${CTX_REMOTE_CLUSTER}" apply -n external-istiod -f \
@samples/multicluster/expose-services.yaml@
{{< /text >}}
### Validate the installation
1. Create, and label for injection, the `sample` namespace on the remote cluster:
{{< text bash >}}
$ kubectl create --context="${CTX_SECOND_CLUSTER}" namespace sample
$ kubectl label --context="${CTX_SECOND_CLUSTER}" namespace sample istio-injection=enabled
{{< /text >}}
1. Deploy the `helloworld` (`v2`) and `sleep` samples:
{{< text bash >}}
$ kubectl apply -f @samples/helloworld/helloworld.yaml@ -l service=helloworld -n sample --context="${CTX_SECOND_CLUSTER}"
$ kubectl apply -f @samples/helloworld/helloworld.yaml@ -l version=v2 -n sample --context="${CTX_SECOND_CLUSTER}"
$ kubectl apply -f @samples/sleep/sleep.yaml@ -n sample --context="${CTX_SECOND_CLUSTER}"
{{< /text >}}
1. Wait a few seconds for the `helloworld` and `sleep` pods to be running with sidecars injected:
{{< text bash >}}
$ kubectl get pod -n sample --context="${CTX_SECOND_CLUSTER}"
NAME READY STATUS RESTARTS AGE
helloworld-v2-54df5f84b-9hxgw 2/2 Running 0 10s
sleep-557747455f-wtdbr 2/2 Running 0 9s
{{< /text >}}
1. Send a request from the `sleep` pod to the `helloworld` service:
{{< text bash >}}
$ kubectl exec --context="${CTX_SECOND_CLUSTER}" -n sample -c sleep \
"$(kubectl get pod --context="${CTX_SECOND_CLUSTER}" -n sample -l app=sleep -o jsonpath='{.items[0].metadata.name}')" \
-- curl -sS helloworld.sample:5000/hello
Hello version: v2, instance: helloworld-v2-54df5f84b-9hxgw
{{< /text >}}
1. Confirm that when accessing the `helloworld` application several times through the ingress gateway, both version `v1`
and `v2` are now being called:
{{< text bash >}}
$ for i in {1..10}; do curl -s "http://${GATEWAY_URL}/hello"; done
Hello version: v1, instance: helloworld-v1-776f57d5f6-s7zfc
Hello version: v2, instance: helloworld-v2-54df5f84b-9hxgw
Hello version: v1, instance: helloworld-v1-776f57d5f6-s7zfc
Hello version: v2, instance: helloworld-v2-54df5f84b-9hxgw
...
{{< /text >}}
## Cleanup
Clean up the external control plane cluster:
{{< text bash >}}
$ kubectl delete -f external-istiod-gw.yaml --context="${CTX_EXTERNAL_CLUSTER}"
$ istioctl uninstall -y --purge --context="${CTX_EXTERNAL_CLUSTER}"
$ kubectl delete ns istio-system external-istiod --context="${CTX_EXTERNAL_CLUSTER}"
$ rm controlplane-gateway.yaml external-istiod.yaml external-istiod-gw.yaml
{{< /text >}}
Clean up the remote config cluster:
{{< text bash >}}
$ kubectl delete ns sample --context="${CTX_REMOTE_CLUSTER}"
$ istioctl manifest generate -f remote-config-cluster.yaml --set values.defaultRevision=default | kubectl delete --context="${CTX_REMOTE_CLUSTER}" -f -
$ kubectl delete ns external-istiod --context="${CTX_REMOTE_CLUSTER}"
$ rm remote-config-cluster.yaml istio-ingressgateway.yaml
$ rm istio-egressgateway.yaml eastwest-gateway-1.yaml || true
{{< /text >}}
Clean up the optional second remote cluster if you installed it:
{{< text bash >}}
$ kubectl delete ns sample --context="${CTX_SECOND_CLUSTER}"
$ istioctl manifest generate -f second-remote-cluster.yaml | kubectl delete --context="${CTX_SECOND_CLUSTER}" -f -
$ kubectl delete ns external-istiod --context="${CTX_SECOND_CLUSTER}"
$ rm second-remote-cluster.yaml eastwest-gateway-2.yaml
{{< /text >}}
Reference in New Issue View Git Blame Copy Permalink