# How to use Checkly with Inlets tunnel for monitoring on-prem services

In this tutorial, I want to show you how to use inlets tunnel with Checkly.

The idea behind this, is to show how to we can use inlets to create tunnel from our on-premise to use a pure SaaS solution like Checkly to monitor the on-prem application

## Checkly

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1630336907450/5aw9FaUXq.png)

[Checkly](https://www.checklyhq.com/) is the API & E2E monitoring platform for the modern stack: programmable, flexible
and loving JavaScript.

You can create a [free account](https://app.checklyhq.com/signup) and start creating cool API and Browser Checks. You can run your checks from over 20 locations worldwide. It has great CI / CD integrations and much more under the hood.

You should go and check it out.

## Inlets

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1630337100885/qKnjJhoz9.png)

For anyone not familiar with inlets. It's a project from [Alex Ellis](https://twitter.com/alexellisuk), a CNCF
Ambassador and the Founder of OpenFaaS.

> Cloud Native Tunnel You can use inlets to connect HTTP and TCP services between networks securely. Through an encrypted websocket, inlets can penetrate firewalls, NAT, captive portals, and other restrictive networks lowering the barrier to entry.
>
>VPNs traditionally require up-front configuration like subnet assignment and ports to be opened in firewalls. A tunnel with inlets can provide an easy-to-use, low-maintenance alternative to VPNs and other site-to-site networking solutions.

### Let's roll

We're going to use `Task` here to quickly spin up the necessary tools. `Task` is a task runner / build tool that aims to be simpler and easier to use than, for example, GNU Make.

Since it’s written in Go, Task is just a single binary and has no other dependencies, which means you don’t need to mess with any complicated install setups just to use a build tool.

#### Install Taskfile

Check the [installation](https://taskfile.dev/#/installation?id=installation) for more installation options. Here I use brew.

    brew install go-task/tap/go-task

#### Mock the on-prem service.

The task `k8s-init-sock-shop` installs the [Weaveworks Sock Shop](https://microservices-demo.github.io/) to mock an application running on-prem. I install it on a k3s via `Rancher Desktop`

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1630337494441/hJwLSPZKD.png)

```yaml
  k8s-init-sock-shop:
    desc: install the sock shop
    cmds:
      - kubectl get nodes
      - kubectl apply -f https://raw.githubusercontent.com/microservices-demo/microservices-demo/master/deploy/kubernetes/complete-demo.yaml
      - kubectl apply -f socks-ingress.yaml
```
Rancher Desktop, as it is k3s, has traefik ingress controller inbouild. So we just need to deploy the ingress resource. 

#### Deploy everything

Just type:

```shell
task
```

To deploy the default task, which is a composition of:

```shell
  default:
    cmds:
      - task: init-checkly
      - task: k8s-init-sock-shop
      - task: inlets-operator
      - task: checkly-terraform
```

We deploy inlets via the inlets-operator on our kubernetes cluster. As an exit-node provider, we are going to use [scaleway](https://www.scaleway.com/en/) for this.

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1630336970316/X-qGWaSRA.png)

Genereate the [API key](https://www.scaleway.com/en/docs/console/my-project/how-to/generate-api-key/), as we going to pass them to the `inlets-operator` via parameter.

```shell
inlets-operator:
    desc: install the inlets operator
    cmds:
      - kubectl apply -f https://raw.githubusercontent.com/inlets/inlets-operator/master/artifacts/crds/inlets.inlets.dev_tunnels.yaml
      - helm repo add inlets https://inlets.github.io/inlets-operator/
      - helm repo update
      - kubectl create secret generic inlets-access-key --from-literal inlets-access-key=$ACCESS_KEY
      - kubectl create secret generic inlets-secret-key --from-literal inlets-secret-key=$SECRET_KEY
      - helm upgrade inlets-operator --install inlets/inlets-operator --set provider=scaleway,region=nl-ams-1 --set secretKeyFile=/var/secrets/inlets/secret/inlets-secret-key --set organizationID=$ORGANISATION_ID --set inletsProLicense=$LICENSE
```

#### Checkly Terraform

To define our Checkly checks, we are using the [checkly](https://registry.terraform.io/providers/checkly/checkly/latest)
terraform provider. So change the `terraform.tfvars.changme` to `terraform.tfvars` in the `checkly-tf` folder and put
the checkly API key into it.

Or use the task:

```shell
task tfvars
```
If everything goes well, you should see following checks on the Checkly Dashboard:

![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1630337206980/99kU3ggwF.png)

In this example i created a API check and a browser check.

Check the great [docs](https://www.checklyhq.com/docs) for more details on Checkly.

#### Clean up

Just call 

```shell
task destroy
```
to remove all checks and delete the exit node and the operator.

Le code -> https://github.com/dirien/checkly-inlets