podvm: add bootc README.md file

config/peerpods/podvm/bootc/README.md

@@ -0,0 +1,37 @@
+# Image Mode (bootc) PodVM Builds
+
+Image Mode PodVM builds allow the OSC Image Creation mechanism to
+convert and push PodVM images based on pre-created bootc (image
+mode) container images.
+
+## Create PodVM Bootc Container Image Locally
+
+Use Podman to build a PodVM bootc image locally and push it to
+a container registry of your choice.
+```
+IMG=quay.io/example/podvm-bootc
+podman build -f Containerfile.rhel -t ${IMG}
+podman push ${IMG}
+```
+Before applying the KataConfig, ensure your
+`<cloud-provider>-podvm-image-cm` values are configured correctly:
+```
+IMAGE_TYPE: pre-built
+PODVM_IMAGE_URI: ${IMG}
+```
+
+## Create PodVM Bootc Container Image In-Cluster
+
+Use an existing OpenShift cluster to execute the container build
+in-cluster and push the container image to the cluster's internal
+registry:
+```
+oc apply -f podvm-git-buildconfig.yaml
+```
+Before applying the KataConfig, ensure your
+`<cloud-provider>-podvm-image-cm` values are configured correctly:
+```
+IMAGE_TYPE: pre-built
+PODVM_IMAGE_URI: bootc::image-registry.openshift-image-registry.svc:5000/openshift-sandboxed-containers-operator/podvm-bootc
+```
+