CLI-based access

Estimated reading time: 2 minutes

Docker UCP secures your cluster with role-based access control, so that only authorized users can perform changes to the cluster.

For this reason, when running docker commands on a UCP node, you need to authenticate your request using client certificates. When trying to run docker commands without a valid certificate, you get an authentication error:

$ docker ps

x509: certificate signed by unknown authority

There are two different types of client certificates:

  • Admin user certificate bundles: allow running docker commands on the Docker Engine of any node,
  • User certificate bundles: only allow running docker commands through a UCP controller node.

Download client certificates

To download a client certificate bundle, log into the UCP web UI, and navigate to your user profile page.

Click the Create a Client Bundle button, to download the certificate bundle.

Use client certificates

Once you’ve downloaded a client certificate bundle to your local computer, you can use it to authenticate your requests.

Navigate to the directory where you downloaded the user bundle, and unzip it. Then source the env.sh script.

$ unzip ucp-bundle-dave.lauper.zip
$ eval $(<env.sh)

The env.sh script updates the DOCKER_HOST environment variable to make your local Docker CLI communicate with UCP. It also updates the DOCKER_CERT_PATH environment variables to use the client certificates that are included in the client bundle you downloaded.

To verify a client certificate bundle has been loaded and the client is successfully communicating with UCP, look for ucp in the Server Version returned by docker version.

$ docker version --format '{{.Server.Version}}'
ucp/2.0.0

From now on, when you use the Docker CLI client, it includes your client certificates as part of the request to the Docker Engine. You can now use the Docker CLI to create services, networks, volumes and other resources on a swarm managed by UCP.

Download client certificates using the REST API

You can also download client bundles using the UCP REST API. In this example we use curl for making the web requests to the API, and jq to parse the responses.

To install these tools on a Ubuntu distribution, you can run:

$ sudo apt-get update && sudo apt-get install curl jq

Then you get an authentication token from UCP, and use it to download the client certificates.

# Create an environment variable with the user security token
$ AUTHTOKEN=$(curl -sk -d '{"username":"<username>","password":"<password>"}' https://<ucp-ip>/auth/login | jq -r .auth_token)

# Download the client certificate bundle
$ curl -k -H "Authorization: Bearer $AUTHTOKEN" https://<ucp-ip>/api/clientbundle -o bundle.zip

Where to go next

Rate this page:

 
0
 
0