open-consul/website/pages/docs/k8s/connect/terminating-gateways.mdx

238 lines
6.9 KiB
Plaintext
Raw Normal View History

---
layout: docs
page_title: Terminating Gateways - Kubernetes
sidebar_title: Terminating Gateways
description: Configuring Terminating Gateways on Kubernetes
---
# Terminating Gateways on Kubernetes
-> 1.8.0+: This feature is available in Consul versions 1.8.0 and higher
-> 0.16.0+: This feature is available in consul-k8s versions 0.16.0 and higher
~> This topic requires familiarity with [Terminating Gateways](/docs/connect/terminating-gateway).
Terminating gateways are a new feature included in Consul 1.8. The correlating consul-k8s binary version is
[0.16.0](https://github.com/hashicorp/consul-k8s/blob/master/CHANGELOG.md#0160-june-17-2020), and is required to enable
terminating gateways. If you are using the latest official [consul-helm chart](https://github.com/hashicorp/consul-helm),
and have not customized the [imageK8S](/docs/k8s/helm#v-global-imagek8s) configuration for any of
your components, you should be running a compatible version by default.
Adding a terminating gateway is a multi-step process:
2020-08-18 22:22:29 +00:00
- Update the helm chart with terminating gateway config options
- Deploying the helm chart
- Accessing the Consul agent
- Register external services with Consul
## Update the helm chart with terminating gateway config options
Minimum required Helm options:
```yaml
global:
name: consul
connectInject:
enabled: true
terminatingGateways:
enabled: true
```
## Deploying the helm chart
Ensure you have the latest consul-helm chart and install Consul via helm using the following
2020-09-14 17:37:35 +00:00
[guide](/docs/k8s/installation/install#installing-consul) while being sure to provide the yaml configuration
as previously discussed.
## Accessing the Consul agent
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.
```shell-session
$ kubectl port-foward consul-server-0 8500 &
```
2020-08-18 22:22:29 +00:00
If TLS is enabled use port 8501:
2020-08-18 22:22:29 +00:00
```shell-session
$ kubectl port-foward consul-server-0 8501 &
```
-> Be sure the latest consul binary is installed locally on your host.
[https://releases.hashicorp.com/consul/](https://releases.hashicorp.com/consul/)
```shell-session
$ export CONSUL_HTTP_ADDR=http://localhost:8500
```
2020-08-18 22:22:29 +00:00
If TLS is enabled set:
2020-08-18 22:22:29 +00:00
```shell-session
$ export CONSUL_HTTP_ADDR=https://localhost:8501
$ export CONSUL_HTTP_SSL_VERIFY=false
```
2020-08-18 22:22:29 +00:00
If ACLs are enabled also set:
2020-08-18 22:22:29 +00:00
```shell-session
$ export CONSUL_HTTP_TOKEN=$(kubectl get secret consul-bootstrap-acl-token -o jsonpath={.data.token} | base64 -D)
```
## Register external services with Consul
Registering the external services with Consul is a multi-step process:
2020-08-18 22:22:29 +00:00
- Register external services with Consul
- Update the terminating gateway ACL token if ACLs are enabled
- Create the configuration entry for the terminating gateway
- Create intentions to allow access from services in the mesh to external service
- Define upstream annotations for any services that need to talk to the external services
### Register external services with Consul
Create a sample external service and register it with Consul.
2020-08-18 22:22:29 +00:00
```json
{
2020-08-18 22:22:29 +00:00
"Node": "legacy_node",
"Address": "example.com",
"NodeMeta": {
"external-node": "true",
"external-probe": "true"
},
"Service": {
"ID": "example-https",
"Service": "example-https",
"Port": 443
}
}
```
Register the external service with Consul:
2020-08-18 22:22:29 +00:00
```shell-session
$ curl --request PUT --data @external.json -k $CONSUL_HTTP_ADDR/v1/catalog/register
```
2020-08-18 22:22:29 +00:00
If ACLs and TLS are enabled :
2020-08-18 22:22:29 +00:00
```shell-session
$ curl --request PUT --header "X-Consul-Token: $CONSUL_HTTP_TOKEN" --data @external.json -k $CONSUL_HTTP_ADDR/v1/catalog/register
```
### Update terminating gateway ACL token if ACLs are enabled
2020-08-18 22:22:29 +00:00
If ACLs are enabled, update the terminating gateway acl token to have `service: write` permissions on all of the services
being represented by the gateway:
2020-08-18 22:22:29 +00:00
- Create a new policy that includes these permissions
- Update the existing token to include the new policy
~> The CLI command should be run with the `-merge-policies`, `-merge-roles` and `-merge-service-identities` so
nothing is removed from the terminating gateway token
```hcl
service "example-https" {
policy = "write"
}
```
2020-08-18 22:22:29 +00:00
```shell-session
$ consul acl policy create -name "example-https-write-policy" -rules @write-policy.hcl
```
2020-08-18 22:22:29 +00:00
Now fetch the id of the terminating gateway token
2020-08-18 22:22:29 +00:00
```shell-session
$ consul acl token list | grep terminating-gateway-terminating-gateway-token
```
2020-08-18 22:22:29 +00:00
Update the terminating gateway acl token with the new policy
2020-08-18 22:22:29 +00:00
```shell-session
$ consul acl token update -id <token-id> -policy-name example-https-write-policy -merge-policies -merge-roles -merge-service-identities
```
### Create the configuration entry for the terminating gateway
2020-08-18 22:22:29 +00:00
Once the tokens have been updated, next write the Consul [config](/docs/agent/config-entries/terminating-gateway)
entry for the terminating gateway:
2020-08-18 22:22:29 +00:00
```hcl
Kind = "terminating-gateway"
Name = "terminating-gateway"
Services = [
{
Name = "example-https"
CAFile = "/etc/ssl/cert.pem"
}
]
```
2020-08-18 22:22:29 +00:00
~> If TLS is enabled a `CAFile` must be provided, it must point to the system trust store of the terminating gateway
container.
Submit the terminating gateway entry with the Consul CLI using this command.
2020-08-18 22:22:29 +00:00
```shell-session
$ consul config write terminating-gateway.hcl
```
If using ACLs and TLS, create intentions to allow access from services in the mesh to the external service
2020-08-18 22:22:29 +00:00
```shell-session
$ consul intention create -allow static-client example-https
```
### Define the external services as upstreams for services in the mesh
2020-08-18 22:22:29 +00:00
Finally define and deploy the external services as upstreams for the internal mesh services that wish to talk to them.
An example deployment is provided which will serve as a static client for the terminating gateway service.
```yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: static-client
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: static-client
spec:
replicas: 1
selector:
matchLabels:
app: static-client
template:
metadata:
name: static-client
labels:
app: static-client
annotations:
2020-08-18 22:22:29 +00:00
'consul.hashicorp.com/connect-inject': 'true'
'consul.hashicorp.com/connect-service-upstreams': 'example-https:1234'
spec:
containers:
# This name will be the service name in Consul.
- name: static-client
image: tutum/curl:latest
2020-08-18 22:22:29 +00:00
command: ['/bin/sh', '-c', '--']
args: ['while true; do sleep 30; done;']
# If ACLs are enabled, the serviceAccountName must match the Consul service name.
serviceAccountName: static-client
```
Run the service via `kubectl apply`:
2020-08-18 22:22:29 +00:00
```shell-session
$ kubectl apply -f static-client.yaml
```
You can verify connectivity of the static-client and terminating gateway via a curl command:
2020-08-18 22:22:29 +00:00
```shell-session
$ kubectl exec deploy/static-client -- curl -vvvs -H "Host: example-https.com" http://localhost:1234/
```