NO-JIRA: docs: devel: create platform external cluster (#175)

**What this PR does / why we need it**:

Add devel document fragment to be used as a helper to deploy platform
external clusters (reusing from CI scripts) to manipulate opct and test
tooling.

**Which issue(s) this PR fixes** *(optional, use `fixes
#<issue_number>(, fixes #<issue_number>, ...)` format, where
issue_number might be a GitHub issue, or a Jira story*:
Fixes #

**Checklist**
- [x] Subject and description added to both, commit and PR.
- [x] Relevant issues have been referenced.
- [x] This change includes docs. 
- [ ] This change includes unit tests.

Author: mtulio

docs/devel/create-cluster-external.md

@@ -0,0 +1,154 @@
+# Create OpenShift Cluster Platform Type External
+
+!!! warn "Development Reference"
+    This guide is intended for developers/builders who want to quickly install OpenShift clusters using a configuration commonly employed for provider validation: the platform-agnostic installation method.
+
+This document explains how to create a cluster using platform type `External`
+for your development environment to quickly test OPCT with OpenShift
+clusters using the platform-agnostic installation method.
+
+OpenShift cluster installations with platform type `External`
+are the primary use case for the OPCT tool, as it validates standalone
+installations to ensure that non-integrated providers
+are correctly setting up the infrastructure required for OpenShift/OKD.
+
+The platform type `External` is based on platform-agnostic installations.
+You can find more details in the
+[Installing a cluster with Platform External](https://docs.providers.openshift.org/platform-external/installing/) documentation.
+
+Platform-agnostic installations require the user to provide the infrastructure,
+with no infrastructure automation by the `openshift-install` program. The
+steps in this guide reuse the infrastructure automation created for OpenShift CI (hosted in the `release` repository).
+The `release-devenv` project reproduces workflows from the `release` repository locally,
+saving time during the installation process.
+
+This guide uses AWS as the provider to install an OpenShift cluster with platform
+type `External`, leveraging existing automation described in the docs.providers documentation to prepare the cluster.
+
+Here is how this document is organized:
+
+- Section 1: Install OpenShift cluster with platform type `External`
+- Section 2: Run OPCT
+
+## Section 1: Install OpenShift Cluster
+
+### Prerequisites
+
+Create the AWS credentials to `${HOME}/.aws/opct`. Make sure it will use the default profile, such as:
+
+```sh
+$ cat ${HOME}/.aws/opct
+[opct]
+aws_access_key_id = <access id>
+aws_secret_access_key = <access key>
+```
+
+Setup release-devenv project:
+
+> See the docs for more information: https://github.com/openshift-splat-team/release-devenv/blob/main/docs/examples/openshift-e2e-external-aws.md
+
+```sh
+export AWS_REGION='us-west-2'
+export CLUSTER_BASE_DOMAIN="opct.devcluster.openshift.com"
+
+export WORKDIR="${HOME}/openshift-labs/external-opct"
+export RELEASE_REPO_PATH="${WORKDIR}/release"
+export RELEASE_DEV_REPO_PATH="${WORKDIR}/release-devenv"
+
+export OCP_RELEASE=4.18
+export OCP_VERSION=4.18.5
+
+# Clone required repos
+git clone [email protected]:openshift/release ${RELEASE_REPO_PATH}
+git clone [email protected]:openshift-splat-team/release-devenv ${RELEASE_DEV_REPO_PATH}
+
+# Install devenv dependencies
+python -m venv ${WORKDIR}/venv && source ${WORKDIR}/venv/bin/activate
+pip install -r ${RELEASE_DEV_REPO_PATH}/requirements.txt
+
+# Create environment variables for release-devenv
+cat << EOF > ${RELEASE_DEV_REPO_PATH}/.env
+# Required by runner
+PULL_SECRET_FILE    = ${PULL_SECRET_FILE}
+RELEASE_REPO_PATH   = ${RELEASE_REPO_PATH}
+SSH_PRIVATE_KEY     = '${HOME}/.ssh/id_rsa'
+SSH_PUBLIC_KEY      = '${HOME}/.ssh/id_rsa.pub'
+AWS_CREDENTIAL_PATH = '${HOME}/.aws/opct'
+
+SKIP_STEPS=ipi-install-rbac,openshift-cluster-bot-rbac
+
+## Required by runner to simulate workflows
+CLUSTER_NAME          = ${USER}-ext-opct2
+BASE_DOMAIN           = ${CLUSTER_BASE_DOMAIN}
+LEASED_RESOURCE       = $AWS_REGION
+JOB_NAME              = 'periodic-ci-openshift-release-master-nightly-${OCP_RELEASE}-e2e-external-aws-ccm'
+CLUSTER_TYPE          = 'aws'
+PERSISTENT_MONITORING = 'no'
+OCP_ARCH              = 'amd64'
+
+# Override globals
+RELEASE_IMAGE                            = 'quay.io/openshift-release-dev/ocp-release:${OCP_VERSION}-x86_64'
+RELEASE_IMAGE_LATEST                     = 'quay.io/openshift-release-dev/ocp-release:${OCP_VERSION}-x86_64'
+OPENSHIFT_INSTALL_RELEASE_IMAGE_OVERRIDE = 'quay.io/openshift-release-dev/ocp-release:${OCP_VERSION}-x86_64'
+
+# Required by workflow/chain/step
+AWS_REGION                    = ${AWS_REGION}
+PROVIDER_NAME                 = 'aws'
+PLATFORM_EXTERNAL_CCM_ENABLED = 'yes'
+
+REGISTRY_AUTH_FILE = ${RELEASE_DEV_REPO_PATH}/volumes/__runtime__/shared/pull-secret-with-ci
+AWS_SHARED_CREDENTIALS_FILE = ${RELEASE_DEV_REPO_PATH}/volumes/cluster-profile/.awscred
+EOF
+
+# ensure .env is created with all variables
+```
+
+### Run the Installation steps
+
+The installation steps are defined on [platform-external-cluster-aws-pre](https://steps.ci.openshift.org/chain/platform-external-cluster-aws-pre)
+
+```sh
+cd ${RELEASE_DEV_REPO_PATH}
+./ci-runner.py --init --run-chain platform-external-cluster-aws-pre
+```
+
+## Section 2: Explore conformance test tooling
+
+Prerequisites:
+
+- OpenShift cluster installed
+- opct installed
+
+
+### Explore OPCT
+
+Sample/simple steps to schedule conformance workflows/jobs to the target cluster using OPCT:
+
+```sh
+opct adm dedicated-node setup
+opct run -w
+opct retrieve
+opct report -s ./results *.tar.gz
+```
+
+### Explore openshift-tests
+
+Steps to perform individual tests using the `openshift-tests` utility:
+
+- Set up a dedicated node
+- Extract `openshift-tests`
+- Create the test list
+- Run the test
+
+```sh
+# Extract openshift-tests https://docs.providers.openshift.org/platform-external/e2e-testing/#openshift-tests-utility
+
+# Run
+test_id=OCPBUGS
+variant=ext-ctrl
+./openshift-tests run \
+-f test-${test_id}.txt \
+--monitor="etcd-log-analyzer" \
+--junit-dir=./test-${test_id}_${variant} \
+| tee -a test-${test_id}_${variant}.txt
+```

mkdocs.yml

@@ -86,6 +86,7 @@ nav:
     - BYO Plugin: devel/byo-plugin.md
     #- Repositories: devel/repositories.md
     - Architectures: devel/arch-support.md
+    - "Devel Guide: Creating cluster with platform type External": devel/create-cluster-external.md
   - Release Notes:
     # TODO: Create release note file document with summary updates by release.
     - CHANGELOG.md