From 923b7d0db64ae8503bb9df4d428143e2c2b00306 Mon Sep 17 00:00:00 2001 From: boruszak Date: Tue, 14 Jun 2022 16:33:29 -0500 Subject: [PATCH] Cluster Peering on Kubernetes initial draft --- .../docs/connect/cluster-peering/k8s.mdx | 187 ++++++++++++++++++ 1 file changed, 187 insertions(+) diff --git a/website/content/docs/connect/cluster-peering/k8s.mdx b/website/content/docs/connect/cluster-peering/k8s.mdx index e69de29bb2..95d4ad3e22 100644 --- a/website/content/docs/connect/cluster-peering/k8s.mdx +++ b/website/content/docs/connect/cluster-peering/k8s.mdx @@ -0,0 +1,187 @@ +--- +layout: docs +page_title: Cluster Peering on Kubernetes +description: >- + This page describes how to create peering connections, deploy services, export cluster services, and end peering connections for Consul cluster peering using Kubernetes (K8s). +--- + +# Cluster Peering on Kubernetes + +~> This page covers features that are currently in _technical preview_. Features and functionality are subject to change. You should never use the technical preview release in secure environments or production scenarios. Features in technical preview may face performance and scaling issues, with limited support options available. + +To establish a cluster peering connection on Kubernetes, you need to enable the feature in the Helm chart, and create custom resource definitions for each side of the peering. + +The following Custom Resource Definitions (CRDs) are used to create and manage a peering connection: + +- `PeeringAcceptor`: Generates a peering token and accepts an incoming peering connection. +- `PeeringDialer`: Uses a peering token to make an outbound peering connection with the cluster that generated the token. + +## Prerequisites + +To create and use cluster peering connections with Kubernetes, you need at least two Kubernetes clusters running in a flat network with Consul on Kubernetes v. 0.45 or later. + +### Helm chart configuration +To establish cluster peering through Kubernetes, deploy clusters with the following Helm values. + +```yaml +global: + peering: + enabled: true +connectInject: + enabled: true +meshGateway: + enabled: true + replicas: 1 +``` + +## Create a peering connection + +To peer Kubernetes clusters running Consul, you need to create a peering token and share it with the other cluster. + +1. In “cluster-01,” create the `PeeringAcceptor` custom resource. + + ```yaml + apiVersion: consul.hashicorp.com/v1alpha1 + kind: PeeringAcceptor + metadata: + name: cluster-02 ## The name of the peer you want to connect to + spec: + peer: + secret: + name: "peering-token" + key: "data" + backend: "kubernetes" + ``` + +1. Apply the `PeeringAcceptor` resource to the first cluster. + + ```shell-session + $ kubectl apply -f acceptor.yml + ```` + +1. Save your peering token so that you can export it to the second cluster. + + ```shell-session + $ kubectl get secret peering-token -o yaml > peering-token.yml + ``` + +1. Apply the peering token to the second cluster. + + ```shell-session + $ kubectl apply -f peering-token.yml + ``` + +1. In “cluster-02,” create the `PeeringDialer` custom resource. + + ```yaml + apiVersion: consul.hashicorp.com/v1alpha1 + kind: PeeringDialer + metadata: + name: cluster-01 ## The name of the peer you want to connect to + spec: + peer: + secret: + name: "peering-token" + key: "data" + backend: "kubernetes" + ``` + +1. Apply the `PeeringDialer` resource to the second cluster. + + ```shell-session + $ kubectl apply -f dialer.yml + ``` + +## Deploy and export cluster services + +1. For the service in “cluster-02” that you want to export, add the following [annotations to your service files](/docs/k8s/annotations-and-labels#consul-hashicorp-com-connect-service-upstreams). + + ```yaml + … + annotations: + "consul.hashicorp.com/connect-inject": "true" + "consul.hashicorp.com/transparent-proxy": "false" + … + ``` + +1. In “cluster-02,” create an `ExportedServices` custom resource. + + ```yaml + apiVersion: consul.hashicorp.com/v1alpha1 + kind: ExportedServices + metadata: + name: default ## The name of the partition containing the service + spec: + services: + name: backend-service ## The name of the service you want to export + consumers: + peerName: cluster-01 ## The name of the peer that receives the service + ``` + +1. Create service intentions for the second cluster. + + ```yaml + apiVersion: consul.hashicorp.com/v1alpha1 + kind: ServiceIntentions + metadata: + name: backend-deny + spec: + destination: + name: backend-service + sources: + - name: "*" + action: deny + - name: frontend-service + action: allow + ``` + +1. Apply the service file, the `ExportedServices` resource, and the intentions in the second cluster. + + ```shell-session + $ kubectl apply -f backend-service.yml; kubectl apply -f exportedsvc.yml; kubectl apply -f intention.yml + ``` + +1. To confirm that you peered your clusters, in “cluster-01,” query the `/health` HTTP endpoint. + + ```shell-session + $ curl "localhost:8500/v1/health/connect/backend?peer=cluster-02" + ``` + +1. For the services in “cluster-01” that you want to access the “backend-service,” add the following annotations to the service file. + + ```yaml + … + annotations: + "consul.hashicorp.com/connect-inject": "true" + "consul.hashicorp.com/transparent-proxy": "false" + "consul.hashicorp.com/connect-service-upstreams": "backend-service.svc.cluster-02.peer:1234" + … + ``` + +1. Apply the service file to the first cluster. + + ```shell-session + $ kubectl apply -f frontend-service.yml + ``` + +1. Run the following command and check the output to confirm that you peered your clusters successfully. + + ```shell-session + $ curl localhost:1234 + { + “name”: “backend-service”, + … + “body”: “Response from backend”, + “code”: 200 + } + ``` + +## End a peering connection + +To end a peering connection, delete both the `PeeringAcceptor` and `PeeringDialer` resources. + +To confirm that you deleted your peering connection, in “cluster-01,” query the `/health` HTTP endpoint. The peered services should no longer appear. + +```shell-session +$ curl "localhost:8500/v1/health/connect/backend?peer=cluster-02" +```