MGMT-22968: Add infrastructure-only mode and Landing Zone VM support

[eliorerz]

This commit adds a new infra_only Makefile target and support for Landing Zone VMs to dev-scripts. This enables users to create baremetal-like test infrastructure (VMs, networks, BMC emulation) without deploying an OpenShift cluster.

Changes:

1. New infra_only Makefile target

   • Runs 'requirements' and 'configure' steps only
   • Stops before cluster deployment (build_installer, ironic, etc.)
   • Useful for testing external deployment tools (GoRI Lab, custom installers)

2. Landing Zone VM support

   • Added NUM_LANDINGZONE environment variable (default: 0)
   • Added landingzone flavor with configurable specs:
     • LANDINGZONE_MEMORY (default: 8192 MB)
     • LANDINGZONE_DISK (default: 60 GB) * LANDINGZONE_VCPU (default: 4)
   • Landing Zone VM acts as deployment host with dual network access

3. Network topology fix for Landing Zone use case

   • Worker VMs: cluster network only (BMC network removed)
   • Landing Zone VM: both BMC and cluster networks
   • Ensures proper network isolation for testing scenarios
   • Only applies when NUM_LANDINGZONE > 0

4. Documentation updates

   • Added "Infrastructure-Only Mode" section to README
   • Added "Deploying with Landing Zone VMs" section to README
   • Documented network topology and use cases

Use case: Testing external deployment tools that need infrastructure without cluster deployment, such as GoRI Lab for bare metal OpenShift installations.

Backward compatibility: All existing targets (default, agent, assisted) work unchanged. New variables default to 0 (no Landing Zone VMs).

[openshift-ci]

Hi @eliorerz. Thanks for your PR.

I'm waiting for a openshift-metal3 member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[eliorerz]

FYI @carbonin

[mkowalski]

/ok-to-test

[mkowalski]

/approve

AFAIK what you call "landing zone vm" is called "bastion host" and "landing zone" itself is "everything in my cloud subscription what can possibly interact with each other.

But it's just a naming so whatever works for you, works

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mkowalski

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[eliorerz]

/retest

[openshift-ci]

@eliorerz: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-agent-ha-dualstack	c132328	link	false	/test e2e-agent-ha-dualstack
ci/prow/e2e-agent-compact-ipv4-iso-no-registry	c132328	link	false	/test e2e-agent-compact-ipv4-iso-no-registry
ci/prow/e2e-metal-ipi-serial-ipv4-2of2	c132328	link	true	/test e2e-metal-ipi-serial-ipv4-2of2

Full PR test history. Your PR dashboard.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.