I am testing the new versions 4.13-9.2 using the osLayering method. Since on Telco env, kernel-rt is required and CGroupV2 support is not yet available for the use cases we have to test, we intend to use the approach of installing kernel-rt in an environment where CGroupV1 has been reactivated. However, it is not possible to get the system to finish booting under these conditions.

413.92.202302031414-0

https://redhat-internal.slack.com/archives/C04MBTXN0KG/p1675871583062239?thread_ts=1675783438.469439&cid=C04MBTXN0KG

1. Install registry.ci.openshift.org/rhcos-devel/ocp-4.13-9.0:4.13.0-ec.1 build

2. Get 413.92.202302031414-0 Base Container Image and deploy it using MC osLayering:

apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
metadata:
  labels:
    machineconfiguration.openshift.io/role: master
  name: sno-osoverride
spec:
  osImageURL: quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:cd4151f0b3e5d51c7b582446d6ea5de06d8afab76ebfcf50c9260e63bafd7591

3. Once installed, apply this MC to reenable cgroups-v1 support:

apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
metadata:
  labels:
    machineconfiguration.openshift.io/role: master
  name: 80-kernelarg-enable-cgroup-v1
spec:
  config:
    ignition:
      version: 3.2.0
  kernelArguments:
    - systemd.unified_cgroup_hierarchy=0
    - systemd.legacy_systemd_cgroup_controller

4. Log in to the server and install kernel-rt:

# sed -i "/\[rt\]/,/\[/  s/enabled=0/enabled=1/" /etc/yum.repos.d/centos-addons.repo
# sed -i "/\[nfv\]/,/\[/  s/enabled=0/enabled=1/" /etc/yum.repos.d/centos-addons.repo
# rpm-ostree override remove kernel{,-core,-modules,-modules-extra} \
    --install kernel-rt-core \
    --install kernel-rt-modules \
    --install kernel-rt-modules-extra \
    --install kernel-rt-kvm

5. reboot

[root@cnfdf23 ~]# journalctl -b -1 |grep -B1 -A4 '2023-02-09 12:41:05.517376369'
Feb 09 12:41:05 cnfdf23.telco5gran.eng.rdu2.redhat.com systemd[1]: Started libcrun container.
Feb 09 12:41:05 cnfdf23.telco5gran.eng.rdu2.redhat.com podman[6417]: 2023-02-09 12:41:05.517376369 +0000 UTC m=+0.117352772 container init 4de14378f0ffe9711b024c608a80a5954a177ee6a61d9de9fb8aff233a6d188e (image=quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:5271b2b0a4f6063170c57c45a16345f2fc0e2f676a260ddc8f916a58ce13e23c, name=gallant_mahavira, health_status=, io.openshift.maintainer.subcomponent=runtime-cfg, io.k8s.display-name=baremetal-runtimecfg, description=Retrieves Node and Cluster information for baremetal network config, io.k8s.description=Retrieves Node and Cluster information for baremetal network config, io.openshift.build.source-location=https://github.com/openshift/baremetal-runtimecfg, io.openshift.expose-services=, release=202212011938.p0.gc508d15.assembly.stream, distribution-scope=public, vendor=Red Hat, Inc., License=GPLv2+, io.openshift.maintainer.product=OpenShift Container Platform, architecture=x86_64, maintainer=Antoni Segura Puimedon <antoni@redhat.com>, summary=Provides the latest release of the Red Hat Extended Life Base Image., vcs-type=git, io.openshift.build.commit.url=https://github.com/openshift/baremetal-runtimecfg/commit/c508d157332b2945f1ecf786be4f193b9e428e51, io.openshift.maintainer.component=Networking, url=https://access.redhat.com/containers/#/registry.access.redhat.com/openshift/ose-baremetal-runtimecfg/images/v4.13.0-202212011938.p0.gc508d15.assembly.stream, build-date=2022-12-01T19:48:29, com.redhat.build-host=cpt-1001.osbs.prod.upshift.rdu2.redhat.com, name=openshift/ose-baremetal-runtimecfg, io.buildah.version=1.27.1, io.openshift.tags=openshift,base, vcs-ref=0ee29b5e2dc48ba09db14731f1fcc2528be978ed, com.redhat.license_terms=https://www.redhat.com/agreements, version=v4.13.0, io.openshift.build.commit.id=c508d157332b2945f1ecf786be4f193b9e428e51, com.redhat.component=ose-baremetal-runtimecfg-container)
Feb 09 12:41:05 cnfdf23.telco5gran.eng.rdu2.redhat.com podman[6417]: 2023-02-09 12:41:05.433618248 +0000 UTC m=+0.033594652 image pull  quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:5271b2b0a4f6063170c57c45a16345f2fc0e2f676a260ddc8f916a58ce13e23c
Feb 09 12:41:05 cnfdf23.telco5gran.eng.rdu2.redhat.com systemd[1]: libpod-4de14378f0ffe9711b024c608a80a5954a177ee6a61d9de9fb8aff233a6d188e.scope: Killing process 6451 (3) with signal SIGKILL.
Feb 09 12:41:05 cnfdf23.telco5gran.eng.rdu2.redhat.com systemd[1]: libpod-4de14378f0ffe9711b024c608a80a5954a177ee6a61d9de9fb8aff233a6d188e.scope: Deactivated successfully.
Feb 09 12:41:05 cnfdf23.telco5gran.eng.rdu2.redhat.com systemd[1]: Stopped libcrun container.

Node should starts