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CodeReady Containers

What is CRC?

CodeReady Containers (CRC) is a minimal, preconfigured OpenShift cluster that is designed to run on your local workstation as a development environment for OpenShift. For more information, see CodeReady Containers.

Similar to Minikube in concept, CRC provides a cloud like environment locally to create and deploy an OpenShift cluster for development and testing purposes.

This page covers some common CRC operations, including deploying Merative Social Program Management (SPM) to the CRC environment. You will use the Helm Charts produced in Preparing Helm Charts.

For a full getting started guide for CRC, see Getting Started Guide CodeReady Containers

Minimum System requirements

CodeReady Containers system requirements can be found here: CRC Minimum system requirements.

There is a known CRC issue with respect to resource usage. When deploying SPM on CRC our experience has shown that a minimum of 16GB will improve performance, however 32GB is optimal.

Red Hat CodeReady Containers only supports platform-native virtualization technologies:

  • HyperKit on macOS
  • libvirt on Linux

Running CRC using nested virtualization is discouraged and not supported.

This Runbook does not support the use of CRC on Windows.

Installing CRC

  • Create an account at RedHat Cloud.

  • Create a $CRC_HOME folder (e.g. ~/crc_home) to use for the purposes of the installation.

  • Download the installation archive from latest release to $CRC_HOME and extract the archive:

    tar -xvf crc-*-amd64.tar.xz

  • On the same page, download your pull secret to $CRC_HOME.

  • Copy the crc binary to /usr/local/bin/

    sudo cp $CRC_HOME/crc-*-amd64/crc /usr/local/bin/

Alternatively, you may add the extracted directory to the $PATH variable instead of moving the binary.

Whichever option you choose, you should now have crc in your executable path. Verify by running the following command:

crc version

The output should be similar to the following:

CodeReady Containers version: 1.23.1+be17b141
OpenShift version: 4.7.0 (embedded in executable)

Setting up CRC

The first step is to configure the prerequisites for the OpenShift cluster, including taking control of your hosts and resolver files to provide access to the CRC cluster. To do this run the following command, providing the workstation administrator password as required. This procedure also creates the ~/.crc directory if it does not already exist.

crc setup

Now that the basic configuration is complete, you need to edit the configuration to change the memory limit and add the path to the pull secret file downloaded previously.

Note: VPN clients can conflict with the network configuration for CodeReady Containers. If you use a VPN client on the same environment as CRC, see the VPN support document in the CRC GitHub wiki.

To change the memory limit, set the CPUs, and add the path to the pull secret file downloaded previously. Run the following commands:

crc config set memory <number-in-MiB>
crc config set cpus <whole-number>
crc config set pull-secret-file $CRC_HOME/pull-secret.txt

CRC’s minimum memory allocation requirement is 8GB, only a single replica SPM deployment can be achieved using this.

You should allocate as many resources as are available.

Note: Values for available memory are set in mebibytes (MiB). Below are some sample values.

Example memory values:

  • 32768 (MiB) is equilivant to 34.4GB
  • 20480 (MiB) is equilivant to 21.5GB
  • 15120 (MiB) is equilivant to 15.9GB

Note: The greater the workload the greater the memory and processor requirements. Any changes to the CRC config require you to delete the cluster and start a new one.

Note: CPU limits must not exceed the physical resources.

You can always check the configured options of crc, run the following command:

crc config view

After setup is complete, start the cluster, run the following command:

crc start

This outputs something similar to the following:

INFO Checking if running as non-root
INFO Checking minimum RAM requirements
INFO Checking if Virtualization is enabled
...
...
Started the OpenShift cluster.


The server is accessible via web console at:
  https://console-openshift-console.apps-crc.testing

Note the kubeadmin and developer credentials for later use.

For convenience, you may set the kubeadmin user’s password as an environment variable:

export KUBEADMN_PSW=kubeadmin-password

In case you need to retrieve the password later, you can run crc console --credentials.

Next, set up the OpenShift Client oc, which is used to administer the CRC cluster:

eval $(crc oc-env)

If required, you can stop the cluster:

crc stop

Or delete the cluster:

crc delete

Creating a CRC project

Create a project for the SPM deployment, again use an environment variable for your convenience when following the guide.

Create the environment variable, you can set to value to anything you like, but it should consist of lower case alphanumeric characters or -, and must start and end with an alphanumeric character (e.g. my-name, or 123-abc):

export PROJECT="ocp"

Log in as kubeadmin:

oc login -u kubeadmin -p $KUBEADMN_PSW https://api.crc.testing:6443

Create the project:

oc new-project $PROJECT

Configuring the Image Registry

CodeReady Containers comes with an internal image registry where you can store the application’s Docker images.

The registry is accessed using different URLs, depending on the use - pods use an internal registry service name, and a developer would use the public route to publish the images.

The registry URLs can be retrieved using the oc registry info command, with either a --public or --internal flag.

  • Public URL: default-route-openshift-image-registry.apps-crc.testing
    • Use this when tagging and publishing images.
  • Internal URL: image-registry.openshift-image-registry.svc:5000
    • Use this when deploying using Helm.

The public URL uses a certificate signed by the OpenShift internal CA, which Docker does not trust by default.

Docker loads all *.crt files under /etc/docker/certs.d/<registryHost[:port]> directories and uses them for verifying any self-signed certificates.

More information can be found in the Docker Documentation Use self-signed certificates.

Enable Docker trust certificate:

CERT_PATH="/etc/docker/certs.d/$(oc registry info --public)"
sudo mkdir -p $CERT_PATH
oc extract secret/router-ca -n openshift-ingress-operator --keys=tls.crt --confirm
sudo cp tls.crt $CERT_PATH

Log in to the OpenShift registry:

docker login -u kubeadmin -p $(oc whoami -t) $(oc registry info --public)

Hostname configuration for CRC

This runbook uses a generic hostname of spm-ocp.apps-crc.testing as an example in commands and the configuration files.

You should add the CRC IP address to the hosts file by using the generic hostname, or else modify the usage of spm-ocp.apps-crc.testing in this runbook to reflect your local hostname.

echo -e "$(crc ip)\tspm-ocp.apps-crc.testing" | sudo tee -a /etc/hosts

Where crc ip is the command that returns the CRC VM’s IP address that is accessible from your workstation.

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