How to adjust the an RHEL CoreOS ISO

Prerequisites

• Red Hat CoreOS ISO
• Latest coreos-installer

Prepare auto-install USB-Sticks including worker igntion

Get worker ignition from running cluster

or use that one created from openshift-install

oc get -n openshift-machine-api \
  secrets/worker-user-data \
  -o go-template="{{ .data.userData | base64decode }}" \
  > worker.ign

Create own rhcos iso

coreos-installer iso customize \
  --dest-device /dev/sda \
  --dest-ignition worker.ign \
  -o ready-to-install-at-sda.iso \
  rhcos-live.x86_64.iso

Option: double check ignition:

coreos-installer iso ignition show ready-to-install-at-sda.iso

Prepare usb stick

dd if=ready-to-install-at-sda.iso of=/dev/$USB_DISK status=progress

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2022-12-17 2020-10-14 Contributors: