Single node cluster (SNC) scripts for OpenShift 4

How to use?

• Make sure the one time system requirements setup is satisfied. (https://github.com/openshift/installer/blob/master/docs/dev/libvirt/README.md#one-time-setup)
• Clone this repo git clone https://github.com/code-ready/snc.git
• cd <directory_to_cloned_repo>
• ./snc.sh

How to create disk image?

• Once your snc.sh script run successfully.
• You need to wait for around 30 mins till cluster settle.
• ./createdisk.sh crc-tmp-install-data

Monitoring

The installation is a long process. It can take up to 45 mins. You can monitor the progress of the installation with kubectl.

$ export KUBECONFIG=<directory_to_cloned_repo>/crc-tmp-install-data/auth/kubeconfig
$ kubectl get pods --all-namespaces

Building SNC for OKD 4

• Before running ./snc.sh, you need to create a pull secret file, and set a couple of environment variables to override the default behavior.
• Select the OKD 4 release that you want to build from: https://origin-release.apps.ci.l2s4.p1.openshiftapps.com
• For example, to build release: 4.6.0-0.okd-2021-01-23-132511

# Create a pull secret file

cat << EOF > /tmp/pull_secret.json
{"auths":{"fake":{"auth": "Zm9vOmJhcgo="}}}
EOF

# Set environment for OKD build
export OKD_VERSION=4.6.0-0.okd-2021-01-23-132511
export OPENSHIFT_PULL_SECRET_PATH="/tmp/pull_secret.json"

# Build the Single Node cluster
./snc.sh

• When the build is complete, create the disk image as described below.

export BUNDLED_PULL_SECRET_PATH="/tmp/pull_secret.json"
./createdisk.sh crc-tmp-install-data

Troubleshooting

OpenShift installer will create 2 VMs. It is sometimes useful to ssh inside the VMs. Add the following lines in your ~/.ssh/config file. You can then do ssh master and ssh bootstrap.

Host master
    Hostname 192.168.126.11
    User core
    IdentityFile <directory_to_cloned_repo>/id_ecdsa_crc
    StrictHostKeyChecking no
    UserKnownHostsFile /dev/null

Host bootstrap
    Hostname 192.168.126.10
    User core
    IdentityFile <directory_to_cloned_repo>/id_ecdsa_crc
    StrictHostKeyChecking no
    UserKnownHostsFile /dev/null

Please note the SNC project is “as-is” on this Github repository. At this time, it is not an offically supported Red Hat solution.