ContainerImage.Pinniped/site/content/docs/concierge-only-demo.md
Monis Khan 89b00e3702
Declare war on namespaces
Signed-off-by: Monis Khan <mok@vmware.com>
2021-02-10 21:52:07 -05:00

8.4 KiB

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Pinniped Concierge Only Demo
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docs

Trying Pinniped Concierge

Prerequisites

  1. A Kubernetes cluster of a type supported by Pinniped as described in architecture.

    Don't have a cluster handy? Consider using kind on your local machine. See below for an example of using kind.

  2. An authenticator of a type supported by Pinniped as described in architecture.

    Don't have an authenticator of a type supported by Pinniped handy? No problem, there is a demo authenticator available. Start by installing local-user-authenticator on the same cluster where you would like to try Pinniped by following the directions in deploy/local-user-authenticator/README.md. See below for an example of deploying this on kind.

  3. A kubeconfig where the current context points to the cluster and has admin-like privileges on that cluster.

Overview

Installing and trying Pinniped on any cluster will consist of the following general steps. See the next section below for a more specific example of installing onto a local kind cluster, including the exact commands to use for that case.

  1. Install the Pinniped Concierge. See deploy/concierge/README.md.
  2. Download the Pinniped CLI from Pinniped's github Releases page.
  3. Generate a kubeconfig using the Pinniped CLI. Run pinniped get kubeconfig --help for more information.
  4. Run kubectl commands using the generated kubeconfig. The Pinniped Concierge will automatically be used for authentication during those commands.

Example of Deploying on kind

kind is a tool for creating and managing Kubernetes clusters on your local machine which uses Docker containers as the cluster's "nodes". This is a convenient way to try out Pinniped on a local non-production cluster.

The following steps will deploy the latest release of Pinniped on kind using the local-user-authenticator component as the authenticator.

  1. Install the tools required for the following steps.

    • Install kind, if not already installed. e.g. brew install kind on MacOS.

    • kind depends on Docker. If not already installed, install Docker, e.g. brew cask install docker on MacOS.

    • This demo requires kubectl, which comes with Docker, or can be installed separately.

    • This demo requires a tool capable of generating a bcrypt hash in order to interact with the webhook. The example below uses htpasswd, which is installed on most macOS systems, and can be installed on some Linux systems via the apache2-utils package (e.g., apt-get install apache2-utils).

  2. Create a new Kubernetes cluster using kind create cluster. Optionally provide a cluster name using the --name flag. kind will automatically update your kubeconfig to point to the new cluster as a user with admin-like permissions.

  3. Deploy the local-user-authenticator app. This is a demo authenticator. In production, you would configure an authenticator that works with your real identity provider, and therefore would not need to deploy or configure local-user-authenticator.

    kubectl apply -f https://get.pinniped.dev/latest/install-local-user-authenticator.yaml
    

    The install-local-user-authenticator.yaml file includes the default deployment options. If you would prefer to customize the available options, please see deploy/local-user-authenticator/README.md for instructions on how to deploy using ytt.

    If you prefer to install a specific version, replace latest in the above URL with the version number such as v0.4.1.

  4. Create a test user named pinny-the-seal in the local-user-authenticator namespace.

    kubectl create secret generic pinny-the-seal \
      --namespace local-user-authenticator \
      --from-literal=groups=group1,group2 \
      --from-literal=passwordHash=$(htpasswd -nbBC 10 x password123 | sed -e "s/^x://")
    
  5. Fetch the auto-generated CA bundle for the local-user-authenticator's HTTP TLS endpoint.

    kubectl get secret local-user-authenticator-tls-serving-certificate --namespace local-user-authenticator \
      -o jsonpath={.data.caCertificate} \
      | tee /tmp/local-user-authenticator-ca-base64-encoded
    
  6. Deploy the Pinniped Concierge.

    kubectl apply -f https://get.pinniped.dev/latest/install-pinniped-concierge.yaml
    

    The install-pinniped-concierge.yaml file includes the default deployment options. If you would prefer to customize the available options, please see deploy/concierge/README.md for instructions on how to deploy using ytt.

  7. Create a WebhookAuthenticator object to configure the Pinniped Concierge to authenticate using local-user-authenticator.

    cat <<EOF | kubectl create -f -
    apiVersion: authentication.concierge.pinniped.dev/v1alpha1
    kind: WebhookAuthenticator
    metadata:
      name: local-user-authenticator
    spec:
      endpoint: https://local-user-authenticator.local-user-authenticator.svc/authenticate
      tls:
        certificateAuthorityData: $(cat /tmp/local-user-authenticator-ca-base64-encoded)
    EOF
    
  8. Download the latest version of the Pinniped CLI binary for your platform from Pinniped's latest release.

  9. Move the Pinniped CLI binary to your preferred filename and directory. Add the executable bit, e.g. chmod +x /usr/local/bin/pinniped.

  10. Generate a kubeconfig for the current cluster. Use --static-token to include a token which should allow you to authenticate as the user that you created above.

    pinniped get kubeconfig --static-token "pinny-the-seal:password123" --concierge-authenticator-type webhook --concierge-authenticator-name local-user-authenticator > /tmp/pinniped-kubeconfig
    

    If you are using MacOS, you may get an error dialog that says “pinniped” cannot be opened because the developer cannot be verified. Cancel this dialog, open System Preferences, click on Security & Privacy, and click the Allow Anyway button next to the Pinniped message. Run the above command again and another dialog will appear saying macOS cannot verify the developer of “pinniped”. Are you sure you want to open it?. Click Open to allow the command to proceed.

  11. Try using the generated kubeconfig to issue arbitrary kubectl commands as the pinny-the-seal user.

    kubectl --kubeconfig /tmp/pinniped-kubeconfig get pods -n pinniped-concierge
    

    Because this user has no RBAC permissions on this cluster, the previous command results in the error Error from server (Forbidden): pods is forbidden: User "pinny-the-seal" cannot list resource "pods" in API group "" in the namespace "pinniped". However, this does prove that you are authenticated and acting as the pinny-the-seal user.

  12. As the admin user, create RBAC rules for the test user to give them permissions to perform actions on the cluster. For example, grant the test user permission to view all cluster resources.

    kubectl create clusterrolebinding pinny-can-read --clusterrole view --user pinny-the-seal
    
  13. Use the generated kubeconfig to issue arbitrary kubectl commands as the pinny-the-seal user.

    kubectl --kubeconfig /tmp/pinniped-kubeconfig get pods -n pinniped-concierge
    

    The user has permission to list pods, so the command succeeds this time. Pinniped has provided authentication into the cluster for your kubectl command! 🎉

  14. Carry on issuing as many kubectl commands as you'd like as the pinny-the-seal user. Each invocation will use Pinniped for authentication. You may find it convenient to set the KUBECONFIG environment variable rather than passing --kubeconfig to each invocation.

    export KUBECONFIG=/tmp/pinniped-kubeconfig
    kubectl get namespaces
    kubectl get pods -A
    
  15. Profit! 💰