213 lines
6.9 KiB
Plaintext
213 lines
6.9 KiB
Plaintext
---
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layout: docs
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page_title: Terminating Gateways - Kubernetes
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sidebar_title: Terminating Gateways
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description: Configuring Terminating Gateways on Kubernetes
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---
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# Terminating Gateways on Kubernetes
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-> 1.8.0+: This feature is available in Consul versions 1.8.0 and higher
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-> 0.16.0+: This feature is available in consul-k8s versions 0.16.0 and higher
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~> This topic requires familiarity with [Terminating Gateways](/docs/connect/terminating-gateway).
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Terminating gateways are a new feature included in Consul 1.8. The correlating consul-k8s binary version is
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[0.16.0](https://github.com/hashicorp/consul-k8s/blob/master/CHANGELOG.md#0160-june-17-2020), and is required to enable
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terminating gateways. If you are using the latest official [consul-helm chart](https://github.com/hashicorp/consul-helm),
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and have not customized the [imageK8S](/docs/k8s/helm#v-global-imagek8s) configuration for any of
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your components, you should be running a compatible version by default.
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Adding a terminating gateway is a multi-step process:
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* Update the helm chart with terminating gateway config options
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* Deploying the helm chart
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* Accessing the Consul agent
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* Register external services with Consul
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## Update the helm chart with terminating gateway config options
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Minimum required Helm options:
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```yaml
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global:
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name: consul
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connectInject:
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enabled: true
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terminatingGateways:
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enabled: true
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```
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## Deploying the helm chart
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Ensure you have the latest consul-helm chart and install Consul via helm using the following
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[guide](/docs/k8s/installation/overview#installing-consul) while being sure to provide the yaml configuration
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as previously discussed.
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## Accessing the Consul agent
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You can access the Consul server directly from your host via `kubectl port-forward`. This is helpful for interacting with your Consul UI locally as well as to validate connectivity of the application.
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```shell-session
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$ kubectl port-foward consul-server-0 8500 &
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```
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If TLS is enabled use port 8501:
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```shell-session
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$ kubectl port-foward consul-server-0 8501 &
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```
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-> Be sure the latest consul binary is installed locally on your host.
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[https://releases.hashicorp.com/consul/](https://releases.hashicorp.com/consul/)
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```shell-session
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$ export CONSUL_HTTP_ADDR=http://localhost:8500
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```
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If TLS is enabled set:
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```shell-session
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$ export CONSUL_HTTP_ADDR=https://localhost:8501
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$ export CONSUL_HTTP_SSL_VERIFY=false
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```
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If ACLs are enabled also set:
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```shell-session
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$ export CONSUL_HTTP_TOKEN=$(kubectl get secret consul-bootstrap-acl-token -o jsonpath={.data.token} | base64 -D)
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```
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## Register external services with Consul
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Registering the external services with Consul is a multi-step process:
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* Register external services with Consul
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* Update the terminating gateway ACL token if ACLs are enabled
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* Create the configuration entry for the terminating gateway
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* Create intentions to allow access from services in the mesh to external service
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* Define upstream annotations for any services that need to talk to the external services
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### Register external services with Consul
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Create a sample external service and register it with Consul.
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```json
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{
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"Node": "legacy_node",
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"Address": "example.com",
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"NodeMeta": {
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"external-node": "true",
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"external-probe": "true"
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},
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"Service": {
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"ID": "example-https",
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"Service": "example-https",
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"Port": 443
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}
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}
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```
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Register the external service with Consul:
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```shell-session
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$ curl --request PUT --data @external.json -k $CONSUL_HTTP_ADDR/v1/catalog/register
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```
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If ACLs and TLS are enabled :
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```shell-session
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$ curl --request PUT --header "X-Consul-Token: $CONSUL_HTTP_TOKEN" --data @external.json -k $CONSUL_HTTP_ADDR/v1/catalog/register
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```
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### Update terminating gateway ACL token if ACLs are enabled
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If ACLs are enabled, update the terminating gateway acl token to have `service: write` permissions on all of the services
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being represented by the gateway:
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* Create a new policy that includes these permissions
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* Update the existing token to include the new policy
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~> The CLI command should be run with the `-merge-policies`, `-merge-roles` and `-merge-service-identities` so
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nothing is removed from the terminating gateway token
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```hcl
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service "example-https" {
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policy = "write"
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}
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```
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```shell-session
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$ consul acl policy create -name "example-https-write-policy" -rules @write-policy.hcl
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```
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Now fetch the id of the terminating gateway token
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```shell-session
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$ consul acl token list | grep terminating-gateway-terminating-gateway-token
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```
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Update the terminating gateway acl token with the new policy
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```shell-session
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$ consul acl token update -id <token-id> -policy-name example-https-write-policy -merge-policies -merge-roles -merge-service-identities
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```
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### Create the configuration entry for the terminating gateway
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Once the tokens have been updated, next write the Consul [config](/docs/agent/config-entries/terminating-gateway)
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entry for the terminating gateway:
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```hcl
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Kind = "terminating-gateway"
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Name = "terminating-gateway"
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Services = [
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{
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Name = "example-https"
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CAFile = "/etc/ssl/cert.pem"
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}
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]
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```
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~> If TLS is enabled a `CAFile` must be provided, it must point to the system trust store of the terminating gateway
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container.
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Submit the terminating gateway entry with the Consul CLI using this command.
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```shell-session
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$ consul config write terminating-gateway.hcl
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```
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If using ACLs and TLS, create intentions to allow access from services in the mesh to the external service
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```shell-session
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$ consul intention create -allow static-client example-https
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```
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### Define the external services as upstreams for services in the mesh
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Finally define and deploy the external services as upstreams for the internal mesh services that wish to talk to them.
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An example deployment is provided which will serve as a static client for the terminating gateway service.
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```yaml
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apiVersion: v1
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kind: ServiceAccount
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metadata:
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name: static-client
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---
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apiVersion: apps/v1
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kind: Deployment
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metadata:
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name: static-client
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spec:
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replicas: 1
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selector:
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matchLabels:
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app: static-client
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template:
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metadata:
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name: static-client
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labels:
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app: static-client
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annotations:
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"consul.hashicorp.com/connect-inject": "true"
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"consul.hashicorp.com/connect-service-upstreams": "example-https:1234"
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spec:
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containers:
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# This name will be the service name in Consul.
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- name: static-client
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image: tutum/curl:latest
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command: [ "/bin/sh", "-c", "--" ]
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args: [ "while true; do sleep 30; done;" ]
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# If ACLs are enabled, the serviceAccountName must match the Consul service name.
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serviceAccountName: static-client
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```
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Run the service via `kubectl apply`:
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```shell-session
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$ kubectl apply -f static-client.yaml
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```
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You can verify connectivity of the static-client and terminating gateway via a curl command:
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```shell-session
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$ kubectl exec deploy/static-client -- curl -vvvs -H "Host: example-https.com" http://localhost:1234/
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```
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