docs: OpenShift/RHCOS compatibility template for agent vendors#101
Merged
Conversation
The existing RHCOS docs are written for an operator enabling the path. This is the missing buyer-facing piece: an ISV shipping an eBPF agent to OpenShift customers, who needs to know it loads on the node OS before a support case tells them. OpenShift nodes cannot be approximated. RHCOS is immutable, boots via Ignition, and carries a backported RHEL kernel whose version says nothing useful -- a BPF-LSM program is rejected on OCP 4.14 (RHEL 9.2) and loads on 4.16/4.18 (RHEL 9.4) on the same 5.14 line, and the RHCOS version string encodes the RHEL base rather than the kernel. So neither 'we tested on RHEL 9' nor a kernel version is evidence. Uses the public mirror: the pull secret gates the OpenShift release payload, not the RHCOS boot qcow2, so this needs no subscription. Signed-off-by: ErenAri <erenari27@gmail.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
The RHCOS work so far is documented for an operator enabling the path (
rhcos-openshift.md) and as evidence (evidence-rhcos.md). Neither speaks to the person who actually has the problem: an ISV shipping an eBPF agent to OpenShift customers.This adds that template.
Why OpenShift needs its own template rather than "use the RHEL profile"
OpenShift nodes cannot be approximated. RHCOS is immutable, boots via Ignition rather than cloud-init, and carries a backported RHEL kernel whose version number is not informative. Two findings from the committed evidence:
414.92→ RHEL 9.2,416.94/418.94→ RHEL 9.4.So "we tested on RHEL 9" is not evidence for OpenShift, and neither is
uname -r. Booting the node image is.Practical note
The RHCOS boot images are public — the pull secret gates the OpenShift release payload, not the qcow2 — so this workflow needs no Red Hat subscription. That is what makes it usable in an ISV's own CI rather than only by an operator with entitlements.
Keeps the existing opt-in safety:
BPFCOMPAT_ENABLE_RHCOSstays off by default, so RHCOS is never claimed runnable without a staged image.